Method and apparatus for forming conductor ends

Abstract

In order to be able to produce different hairpin stators more flexibly and process-reliably, a conductor end shaping method and a conductor end shaping device are described, with which the conductor ends of the hairpins, which protrude from the stator slots, are shaped to form the coil winding. In the process, the conductor ends are shaped in the radial direction using different widening tools, in particular grippers, which allow the conductor ends to be engaged, in particular gripped, individually or in pairs, such that a first portion is located in a first radial position, a second portion is located in a second radial position, and a third portion is located in at least one intermediate position therebetween. Subsequently, the conductor ends are shaped in the circumferential direction using twisting tools, the more outwardly located twisting tools having an inner receiving pocket which opens inward, and the more outwardly located twisting tools having an outer receiving pocket which opens outward. At least one twisting tool has inner and outer receiving pockets, one of these sets being located in the at least one intermediate position to shape the third portion of the conductor end.

Description

Technical Field

[0001] This invention relates to a conductor end forming method for forming an axially extending conductor end from an arrangement of stator slots of a stator component extending annularly around a central axis into a stator of an electric motor. The invention also relates to a conductor end forming apparatus for forming an axially extending conductor end from an arrangement of stator slots of a stator component, the stator slots extending annularly around a central axis to form the stator of an electric motor. Background Technology

[0002] For the technical background, please refer to the following literature: [1]WO 2019 / 161832A1 [2]WO 2019 / 161846A1 [3]WO 2020 / 127718A1 [4]DE 102018103930A1 [5]EP 3907864A1 [6]WO 2019 / 114870A1 [7]WO 2018 / 233774A1 [8]WO 2019 / 007459A1 [9]WO 2021 / 026576A1

[10] WO 2019 / 201731A1

[11] DE 102019219481A1 Electric motors are understood in particular as machines used to convert electrical energy into kinetic energy and machines used to convert kinetic energy into electrical energy. Specifically, they are understood to include electric motors and generators.

[0003] In several methods of manufacturing the stator of such an electric motor, the ends of conductors formed by wires are connected to each other or processed together in other ways, such as by cutting or shaping together.

[0004] For example, there exist electric motors in which the coil windings, particularly the stator coil windings, are formed of different conductors, the ends of which are then connected to each other. In particular, devices and methods are known for connecting conductor ends (typically wire ends) in the form of so-called "hairpins" (e.g., conductor pieces bent into a hairpin shape) to form the stator windings of the motor, wherein the conductor ends (also called "pins") are soldered together. Here, devices and methods for positioning and clamping the conductor ends prior to soldering are provided.

[0005] In order to properly weld the wire ends, for example after inserting a hairpin, it is advantageous to first shape the wire ends, in particular by widening and twisting them so that the wire ends protrude from the various slots in the housing of the component, so as to form a pair of wire ends to be connected together.

[0006] Methods and apparatus for performing torsion (forming the conductor end in a circumferential direction relative to the central axis of the component) are known from references [1] to [3]. Before torsion, the conductor end is usually widened (i.e., shaped in the radial direction). Methods and apparatus for widening are known from references [4] and [5] and [9] to

[11] . Therefore, it is known to use a gripper or other widening device as a widening tool. Summary of the Invention

[0007] The technical problem upon which this invention is based is to provide a method and apparatus for forming conductor ends so as to manufacture stators more flexibly and reliably.

[0008] To address this problem, the present invention provides a conductor end forming method according to an embodiment of this application and a conductor end forming apparatus according to another embodiment of this application. Embodiments of this application also relate to a computer program having instructions for performing the conductor end forming process.

[0009] Advantageous design is the subject of embodiments of this application.

[0010] According to a first aspect of the invention, a conductor end forming method is provided for forming a conductor end to form a stator of an electric motor, the conductor end extending axially from an arrangement of stator slots of a stator component extending annularly around a central axis. The conductor end forming method includes: a) The conductor end is widened by using multiple widening tools of a radial bending device, such as a gripper or other widening tool, to bend the conductor end in the radial direction. As a result of the widening, a first portion of the conductor end is located at a first radial position, and a second portion of the conductor end is located at a second radial position. b) The conductor end is twisted by bending it in a circumferential direction using a circumferential bending device having a first bending unit and a second bending unit. The first bending unit is rotatable in a first rotational direction and has a first annular arrangement of receiving bags, and the second bending unit is rotatable in a second rotational direction and has a second annular arrangement of receiving bags concentrically arranged therewith. Step b) includes the following steps: b1) Insert the first portion of the conductor end, which was widened to the first radial position in step a), into the first arrangement of the receiving bag; insert the second portion of the conductor end, which was widened to the second radial position in step a), into the second arrangement of the receiving bag; and b2) Rotate the first bending unit and the second bending unit relative to each other to bend the first portion and the second portion of the conductor end in opposite circumferential directions.

[0011] According to the present invention, step a) includes the following steps: a1) Engaging at least one single conductor end by at least a first widening tool, such as a first gripper, to individually bend the engaged at least one single conductor end in the radial direction, and jointly engaging at least a pair of radially adjacent conductor ends by at least a second widening tool, such as a second gripper, to bend the pair of radially adjacent conductor ends together in the radial direction, wherein step a1) is performed such that a third portion of the conductor end is located at at least one intermediate radial position between the first radial position and the second radial position.

[0012] According to the present invention, step b) includes: b0) Provides first and second bending units such that the bending unit located radially outward has a radially inner receiving bag with an opening toward a radially inner side, and the bending unit located radially outward has a radially outer receiving bag with an opening toward a radially outer side, wherein a portion of the receiving bag of the first arrangement is located at a first radial position, and another portion of the receiving bag of the first arrangement is radially offset to and located at an intermediate radial position, and / or a portion of the receiving bag of the second arrangement is located at a second radial position, and another portion of the receiving bag of the second arrangement is radially offset to and located at an intermediate radial position.

[0013] According to the present invention, step b1) includes: b1a) Insert the conductor end widened to at least one intermediate radial position into the corresponding receiving bag of another portion of the first or second arrangement, and insert the corresponding radial inner conductor end of each pair of conductor ends that are bent together in step a1) into one of the radial outer receiving bags, and insert the radial outer conductor end of the pair of conductor ends into one of the radial inner receiving bags.

[0014] Preferably, step a) includes the following steps: a0) Provide a separate radial bending control dataset for each individual conductor end to be radially bent or for each pair of conductor ends to be bent together, and control the corresponding widening tool, such as the corresponding gripper, individually by means of the radial bending control dataset assigned to the conductor end to be bent.

[0015] Preferably, step a) includes the following steps: a2) Simultaneously using different widening tools in a widening tool set, which includes a single widening tool for joining a single conductor end, a conductor end pair widening tool for joining a pair of conductor ends, and combinations formed at different joining portions and configured for joining a single conductor end and for joining a pair of conductor ends.

[0016] Preferably, step a) includes the following steps: a2a) Simultaneously using different grippers from the gripper group as widening tools, the grippers include a single gripper for gripping a single conductor end, a pair of conductor end grippers for gripping a pair of conductor ends, and a combined gripper formed at different gripping segments for gripping a single conductor end and for gripping a pair of conductor ends.

[0017] Preferably, step a) includes the following steps: a3) Simultaneously engage multiple conductor ends extending from the stator slot at the same radial position using the widening tool, and release the engaged single or paired conductor ends after differential movement in the radial direction, so as to bend the first portion to a first radial position, the third portion to at least one intermediate radial position and the second portion to a second radial position.

[0018] Preferably, step a0 includes the following steps: a0a), generate a radial bending control dataset corresponding to the desired winding scheme of the stator to be manufactured.

[0019] Preferably, step a0) includes the following steps: a0b) Generate a master control dataset for the conductor end or pair of conductor ends to be bent equally to form a group of conductor ends or pairs of conductor ends, and generate an additional control dataset for the group of conductor ends or pairs of conductor ends to be bent equally while copying the master control dataset.

[0020] Preferably, step a0) includes the following steps: a0c) Parameterize the nominal position and radial bending movement of each conductor end to generate a radial bending control dataset.

[0021] Preferably, step b0) includes the following steps: b01) Provides a first torsional crown having an annular wall as a first bending unit, and forms a first arrangement of receiving bags at the axial end of the annular wall, wherein the radially inner receiving bag is formed by an inner groove formed radially inward and opening at the axial end, and the radially outer receiving bag is formed by an outer groove formed radially outward and opening at the axial end.

[0022] Preferably, step b0) includes the following steps: b02) Provides a second torsional crown having an annular wall as a second bending unit, wherein a second arrangement of receiving bags is formed at the axial end of the annular wall, wherein the radially inner receiving bag is formed by an inner groove formed radially inward and opening at the axial end, and the radially outer receiving bag is formed by an outer groove formed radially outward and opening at the axial end.

[0023] In a preferred embodiment, at least one of the torsion crowns is formed with an inner receiving bag and an outer receiving bag. Depending on the design and arrangement, the inner or outer receiving bag may be located at at least one intermediate radial position.

[0024] According to another aspect, the present invention provides a conductor end forming apparatus for forming conductor ends to form a stator of an electric motor, the conductor ends extending axially from an arrangement of stator slots in a stator component, the arrangement of stator slots extending circumferentially about a central axis, the apparatus comprising: A radial bending device for widening a conductor end using multiple widening tools, such as grippers, the widening tools being designed to bend the conductor end in the radial direction such that, after bending, a first portion of the conductor end is located at a first radial position and a second portion of the conductor end is located at a second radial position. A circumferential bending device for twisting a conductor end by bending in a circumferential direction. The circumferential bending device includes a first bending unit and a second bending unit. The first bending unit is rotatable in a first rotational direction and has a first annular arrangement of receiving bags. The second bending unit is concentrically arranged with the first bending unit, rotatable in a second rotational direction, and has a second annular arrangement of receiving bags. Controller, suitable for controlling conductor end forming device to a) The conductor end is widened by bending it radially in the radial direction using multiple widening tools (e.g., grippers) of a radial bending device, such that, as a result of the widening, a first portion of the conductor end is located at a first radial position and a second portion of the conductor end is located at a second radial position. b) The conductor end is twisted by bending it in the circumferential direction using a circumferential bending device. b1) Insert the first portion of the conductor end, which was widened to the first radial position in step a), into the first arrangement of the receiving bag; insert the second portion of the conductor end, which was widened to the second radial position in step a), into the second arrangement of the receiving bag; and b2) Rotate the first bending unit and the second bending unit relative to each other so that the first part of the conductor end and the second part of the conductor end bend in opposite circumferential directions.

[0025] According to the invention, a radially outer bending unit in the first and second bending devices is also provided to have a radially inner receiving bag with an opening toward a radially inner side, and a radially outer bending unit to have a radially outer receiving bag with an opening toward a radially outer side, wherein a portion of the first arranged receiving bag is located at a first radial position, and another portion of the first arranged receiving bag is radially offset to and located at an intermediate radial position, and / or a portion of the second arranged receiving bag is located at a second radial position, and another portion of the second arranged receiving bag is radially offset to and located at an intermediate radial position.

[0026] According to the invention, the controller is also adapted to control the conductor end forming device during the widening process according to step a) for the following purposes a1) By means of at least one first widening tool, such as a first gripper, engaging at least a single conductor end to bend the individually gripped conductor end in the radial direction, and by means of at least a second widening tool, such as a second gripper, jointly engaging at least a pair of radially adjacent conductor ends to bend the pair of radially adjacent conductor ends in the radial direction, the controller is adapted to perform control of the gripper in such a way that a third portion of the conductor end is located at at least one intermediate radial position between the first and second radial positions.

[0027] According to the invention, the controller is also adapted to control the conductor end forming device during insertion according to step b1) to b1a) Insert the conductor end widened to at least one intermediate radial position into the corresponding receiving bag of another part of the first or second arrangement, and insert the corresponding radial inner conductor end of each pair of conductor ends that are bent together in step a1) into one of the radial outer receiving bags, and insert the radial outer conductor end of the pair of conductor ends into one of the radial inner receiving bags.

[0028] Preferably, the controller is adapted to individually control the widening tool, such as a gripper, of the radial bending device based on a separate dedicated radial bending control dataset for each individual conductor end to be radially bent or for each pair of conductor ends to be bent together.

[0029] Preferably, the radial bending device includes different widening tools from a widening tool set, which includes a single widening tool for joining a single conductor end, a conductor end pair widening tool for joining a pair of conductor ends, and a combined widening tool formed at different joining portions for joining a single conductor end and for joining a pair of conductor ends.

[0030] Preferably, the radial bending device has different grippers from a group of grippers that serve as widening tools, including a single gripper for gripping a single conductor end, a pair of conductor end grippers for gripping a pair of conductor ends, and a combined gripper formed at different gripping segments and configured for gripping a single conductor end and for gripping a pair of conductor ends.

[0031] Preferably, the radial bending device has a gripper as a widening tool, the gripper having a first jaw and a second jaw, the first jaw and the second jaw being movable toward each other for gripping and movable away from each other for release, wherein a receiving groove for the conductor end to be gripped is formed on at least one of the jaws between the two shoulders, the receiving groove being designed to engage around a single conductor end in the case of a single gripper and around a pair of conductor ends in the case of a conductor end to a gripper.

[0032] Preferably, the radial bending device has a combined gripper with different gripping segments, one gripping segment being designed to clamp a single conductor, while the other gripping segment is designed to clamp a pair of conductor ends.

[0033] Preferably, the controller is also adapted to control the radial bending device to simultaneously clamp multiple conductor ends extending from the stator slot at the same radial position using a widening tool, and to release the clamped single or paired conductor ends after differential movement in the radial direction, so as to bend a first portion to a first radial position, a third portion to at least one intermediate radial position, and a second portion to a second radial position.

[0034] Preferably, the circumferential bending device has a first torsional crown with an annular wall as a first bending unit, and a first arrangement of receiving bags is formed at the axial end of the annular wall, wherein the radially inner receiving bag is formed by an inner groove formed radially inward and opening at the axial end, and the radially outer receiving bag is formed by a radially outer groove formed radially outward and opening at the axial end.

[0035] Preferably, the circumferential bending device has a second torsional crown with an annular wall as a second bending unit, and a second arrangement of receiving bags is formed at the axial end of the annular wall, wherein the radially inner receiving bag is formed by an inner groove formed radially inward and opening at the axial end, and the radially outer receiving bag is formed by an outer groove formed radially outward and opening at the axial end.

[0036] According to another aspect, the present invention provides a computer program comprising instructions that cause the conductor end forming apparatus according to any of the foregoing embodiments to perform the conductor end forming method according to any of the foregoing embodiments.

[0037] Preferably, the distance between the first radial position and the second radial position is less than twice the radial thickness d of the conductor end measured in the radial direction. Preferably, this distance is less than the radial thickness d of the conductor end.

[0038] Preferably, the intermediate radial position is offset by a factor f in the radial direction relative to the first or second position by an amount of d, where d is the radial thickness of these conductor ends, and f is a factor, where 0.05 < f < 2, preferably 0.1 < f < 1.5, specifically 0.2 < f < 1. Particularly preferably, the intermediate position is at the center between the first position and the second position.

[0039] In the following, some advantages, functions and special features of the preferred embodiments compared with the prior art will be explained in more detail.

[0040] Preferred embodiments of the present invention relate to a method and tool for widening and twisting a stator. Specific embodiments of the present invention relate to the field of manufacturing stators for electric devices.

[0041] Preferably, the radial bending device comprises a combined widening tool, in particular with associated sequential combined grippers for widening. In particular, the sequence of the widening steps is predetermined so as to prepare a subsequent twisting step for implementing a special coil winding.

[0042] Preferably, different widening tools, such as in particular grippers, are used simultaneously to form schemes (individual, in pairs, combined).

[0043] Preferably, parameterization and control of the individual pins are provided via the main pin.

[0044] Preferably, widening to different (radial) positions is performed (engaging / clamping at the same time, but releasing differently, with stopping or in operation).

[0045] Preferably, a twisting tool with a twisting crown having inner and outer grooves is provided. This allows individual pins and pin pairs to be twisted in a manner that is particularly suitable for the desired winding scheme of the stator.

[0046] Preferred embodiments of the invention are used in the subfield of electric motor production, more specifically, in the field of stator production for traction drives (electrically driven vehicles, particularly cars and trucks). In particular, the methods and apparatus according to embodiments of the invention are used for the production of so-called hairpin stators, which protrude from copper flat wires in their characteristic "hairpin" form. Specifically, the hairpin is formed of copper or the like, has a generally rectangular cross-section and an external insulating coating, and has a first leg, a second leg, and a generally roof-shaped bend between the first and second legs, i.e., the so-called winding head. The hairpin is preferably inserted axially, its pins in a core of individual laminations stacked on top of each other, the ends of the pins (examples of conductor ends) protruding beyond the stacked core. The number of slots in the stator can be varied according to the desired number of poles. To generate a rotating field, the straight ends protruding from the stator are interconnected in a specific order such that they form pole pairs with each other. The magnetic field generated by supplying alternating current causes the rotor to rotate due to repulsion or attraction.

[0047] In the production of hairpin stators, conductors are rotated relative to each other to generate electrical flux, thereby forming contact between selected conductor ends. For this purpose, in a first step (referred to as step a above), the conductor ends projecting straight from the laminated core are radially widened. Preferably, the conductor ends are fixed in place by a clamping process and bent outward or inward in the radial direction. The final distance between the individual conductor ends or pairs of conductor ends in the gap facilitates their twisting relative to each other in a subsequent process (referred to as step b above) using a twisting tool (e.g., a circumferential bending device). For this purpose, the widened conductor ends are preferably inserted into a twist crown provided with grooves, which can rotate in any direction. By rotating multiple such twist crowns, certain conductor ends can be positioned relative to each other. Then, for example, by a welding process, the conductor ends (especially wire ends) belonging together can be joined together. To ensure a safe joining process, the distance between the mating parts to be joined must not be too large.

[0048] According to reference [3], the paired conductor ends have been widened together. Then, the widened conductor end pair is twisted using the torsion crowns of the outer and inner grooves. Other widening tools, such as those known from [9] to

[11] , can also be used to widen a single conductor or a group of conductors, especially a pair of conductors.

[0049] In some hairpin stators, there are winding schemes where only paired conductor ends of the common loop extending beyond two adjacent locations are connected. The loops are then electrically connected via special pins or through individual winding heads. Since the winding heads for each hairpin are typically formed before the hairpins are assembled into loops, the cost of producing and supplying hairpins in this case is higher.

[0050] On the other hand, advantageous embodiments of the invention enable winding schemes to be implemented in a flexible and process-safe manner, wherein electrical connections between rings are achieved by connecting at least one conductor end of one ring to at least one conductor end of another ring (achieving position jumps on the torsion side). This is achieved by applying widening and torsion to different conductor ends. Although widening and torsion become slightly more complex, this allows for a reduction in the number of different winding head geometries. Advantageous embodiments of the invention enable increased or enhanced process stability despite more complex widening and torsion, without requiring additional process steps.

[0051] Advantageous embodiments of the invention make the stator manufacturing process more flexible, with stator position jumps achieved by contacting the conductor ends at intermediate positions, thus enabling operation with fewer different winding head geometries. Advantageous embodiments of the invention also enable reliable and precisely positioned widening and torsion processes, even for complex torsional variations, which significantly contributes to increased process stability in subsequent operations. Preferably, the flexible manufacturing process is made possible by a combination of different widening tools, such as tools for individual conductor ends, for conductor end pairs, and combinations thereof (tools for individual conductor ends and for conductor end pairs). Therefore, the torsion tools are preferably also adapted and optimized to given boundary conditions. Preferably, the final position of the stator conductor ends is reproduced as accurately as possible through the widening and torsion processes. In particular, challenges arise due to the numerous variations in stator geometry and electrical connections. Therefore, the tools and process sequences used in the process and apparatus according to the preferred embodiments of the invention can be flexibly adapted to existing workpieces, provided that process stability is improved and at least neutral cycle times are achieved.

[0052] Preferred embodiments of the method and apparatus according to the invention produce a coordinated concept of adaptive tooling and process sequence. By classifying the various widening tools into single widening tools, two widening tools, and combined widening tools, such as, in particular, single, two, and combined grippers, a widening concept suitable for the corresponding desired stator can be established, wherein each widening tool, such as each gripper, can be individually controlled and actuated in each processing step. By combining the different widening tools, such as, in particular, grippers, with a tuned process control system, virtually any interconnection scheme on the torsional side of the stator can be reproduced.

[0053] A particularly preferred embodiment of the method and apparatus according to the invention includes creating a special widening and twisting pattern that directly reflects the electrical interconnections of the stator and can represent conventional and unconventional switching schemes with and without position jumps on the twisting side. Furthermore, multiple diameters can be achieved for each position. Intermediate products as close as possible to the final state can be produced by positioning the pins for the subsequent twisting process using a separately designed twisting tool, which in some particularly preferred embodiments has external and internal grooves on the tool. A key feature is the minimum possible pin spacing between the pin ends of the stator belonging together.

[0054] In the prior art, only sequential widening and twisting operations have been described to date, involving the processing of individual pins or conventional pin pairs. However, no specific reference has been made to the electrical interconnections and pin positions. In a preferred embodiment of the method and apparatus adapted to the invention, the unsoldered ends of the hairpin can be processed with positional accuracy. Thus, during the widening and twisting process, all pins belonging together can be placed together to form a pair. In subsequent processing steps, the mechanical forming or displacement of the pins can be largely eliminated. This, in turn, leads to increased process reliability regarding pin end positioning and thus reduces scrap rates in subsequent processes.

[0055] In the process according to the invention, during widening, some conductor ends are positioned at a first radial position, and some conductor ends are positioned at a second radial position. The conductor ends widened to the first radial position are received for twisting in a first arrangement of the receiving bag on the first bending unit, and the conductor ends widened to the second radial position are received for twisting in a second arrangement of the receiving bag on the second bending unit. Twisting is achieved by relative rotation of the bending unit and thus relative rotation of the first and second arrangements of the receiving bag.

[0056] However, the other conductor end is positioned at an intermediate radial position between the first and second radial positions during widening. This can be achieved, in particular, by engaging the conductor ends in pairs, especially by clamping the conductor ends, or by combining paired and individual engagements, especially by clamping actions.

[0057] In a preferred embodiment, at least one bending unit of the circumferential bending device has inner and outer receiving bags to provide an alternative arrangement of receiving bags at an intermediate radial position, in addition to the arrangement of the associated receiving bags. Depending on the design and arrangement, the inner or outer receiving bag may be located at at least one intermediate radial position. As is substantially known from [3], receiving bags arranged close to each other and open to each other even allow very close adjacent conductor ends to be twisted relative to each other. Thus, in addition to the conductor ends widened to the first and second radial positions, the conductor ends widened to the intermediate radial position can also be reliably twisted.

[0058] This provides a high degree of flexibility for twisting and widening, for example, in a way that the conductor ends to be connected can also be positioned close to each other at an intermediate radial position. Attached Figure Description

[0059] Exemplary embodiments will now be explained in more detail with reference to the accompanying drawings, which illustrate exemplary embodiments. Figure 1 This is a schematic block diagram of an embodiment of a stator manufacturing apparatus for manufacturing an electric motor with coils; Figure 2 This is a schematic plan view of a stator component in the form of the stator core during conductor insertion; Figure 3a , 3b It is a series of steps to insert conductor ends, which are formed by widening and twisting in a conventional manner, into a clamping and fixing device to form a pair of conductor ends to be welded; Figure 4 This is a plan view of the torsion side of a stator component of a first-type stator, which has conductor end pairs to be welded after torsion, wherein position jumps are achieved by separate layer hairpins; Figure 5 It is a plan view of the torsion side of a stator component for a second type of stator, the stator component having a pair of conductor ends to be welded after torsion, wherein a position jump is achieved on the torsion side; Figure 6 This is an axial plan view of the radial bending device of the stator manufacturing apparatus according to a preferred embodiment; Figure 7a , 7b Figure 7c schematically illustrates the clamping process of a first gripper with a first jaw and a second jaw during widening, which is used by means of a radial bending device to clamp a single conductor end. Figure 8 This is a perspective view of the gripper's jaws; Figure 9 This is a perspective view of the gripper of the second gripper of the radial bending device; Figure 10 This is a perspective view of the gripper of the third gripper of the radial bending device; Figure 11 This is a schematic block diagram illustrating examples of the first to fourth different widening sequences used to widen the conductor ends that extend together from the stator slots; Figure 12 This is a perspective view of the bending unit of the torsion crown of a stator manufacturing apparatus designed for torsion; Figure 13 yes Figure 12Detail XIII indicates radially inner and radially outer receiving bags; Figure 14 It is an axial plan view of the end of the first torsion crown, which is provided with a receiving bag and is located in a radially outward position. The conductor end is received in the radially inner and radially outer receiving bags of the first torsion crown, and the radially inward second torsion crown is indicated by a dashed line. Figure 15 This is an illustration of the second torsion crown in its initial position, where the conductor end is received in radially inner and radially outer receiving pockets, and adjacent torsion crowns are indicated by dashed lines; and Figure 16 After the relative movement of adjacent torsion crowns to perform torsion, as Figure 15 The view shown is to form conductor end pairs with a small distance between them. Detailed Implementation

[0060] Below, with reference to the accompanying drawings, preferred designs of apparatus and methods for performing manufacturing steps in the subfield of electric motor production, more precisely in the field of stator production for traction drives, are described.

[0061] exist Figure 1 The diagram illustrates one embodiment of a stator manufacturing apparatus 10 for manufacturing a stator 50 of a motor having coils, and also shows the manufacturing steps of a corresponding stator manufacturing method for manufacturing the stator 50.

[0062] The stator 50 manufactured by the stator manufacturing apparatus 10, especially the stator 50 intended for use as a traction motor in an electric vehicle, is preferably in the power range of 20 kW to 400 kW. For this purpose, the stator 50 should have as many coils as possible, wherein the coils are made of hairpins 12.

[0063] In the illustrated embodiment, the stator manufacturing apparatus 10 includes a conductor end forming apparatus 14, and preferably includes one or more additional stations, which will be described in more detail below.

[0064] Preferably, the stator manufacturing apparatus 10 includes a laminated core manufacturing apparatus 16 for manufacturing stator components 18 of a stator 50, which is formed as a laminated core and will be provided with coils. The laminated core manufacturing apparatus 16 is designed, for example, in a known manner, to manufacture the stator components 18 from individual laminated core layers, wherein the stator components 18 are annularly designed and have a row of stator slots 20 in the inner wall region, these stator slots being distributed on the inner wall and used to accommodate conductor segments.

[0065] Preferably, the stator manufacturing apparatus 10 has a device 22 for generating slot insulation, by which each stator slot 20 is provided with slot insulation 24 preferably made of insulating paper. The device 22 for generating slot insulation is preferably implemented in a manner described in more detail in reference [6].

[0066] The stator manufacturing apparatus 10 also includes a hairpin manufacturing apparatus 26 for manufacturing the hairpin 12. The hairpin manufacturing apparatus 26 may include, for example, a cutting device (not shown) for cutting wires from the coil and a bending device (not shown in more detail) for producing a top bend and / or a kink bend and / or a 3D bend of the hairpin 12.

[0067] Preferably, the stator manufacturing apparatus 10 includes a prepositioning device 28 for prepositioning the hair clip 12 and a hair clip insertion device 30 for inserting the prepositioned hair clip 12 into a stator slot 20 of the laminated core 18. Possible embodiments of the prepositioning device 28 and the hair clip insertion device 30 are shown and described in more detail in reference [7]. In particular, in the prepositioning device 28, the hair clip 12 is prepositioned to form a ring.

[0068] As shown in the hairpin manufacturing device 26, the hairpin 12 has a curved winding head 32 and two leads with free lead wire ends 34, which are provided with an insulator, such as a plastic coating, except for the outermost end region at each lead wire end 34. After the hairpin is inserted by the hairpin insertion device 30, the lead wire ends 34 extend from the stator slot 20 at one end (torsion side 52) of the stator component 18.

[0069] The conductor end forming device 14 is used to perform a widening process in which each conductor end 34 is widened in the radial direction, and to perform a torsion process in which the widened conductor ends 34 are formed in the circumferential direction to form a pair of corresponding conductor ends 34 to be connected to each other.

[0070] For this purpose, the conductor end forming apparatus 14 has a radial bending device 36 and a circumferential bending device 38. Furthermore, the conductor end forming apparatus 14 includes a controller 54. The controller 54 may be part of the central control system of the stator manufacturing apparatus 10, or a separate distributed controller 54 for the conductor end forming apparatus 14. The controller 54 is configured as an electronic controller with a memory into which a corresponding computer program for executing the conductor end forming process is loaded, as will be discussed in more detail later.

[0071] The stator manufacturing apparatus 10 may also include clamping and / or fixing devices 40 for clamping and / or fixing the individual conductor end pairs 34 to be connected. An embodiment of the clamping and fixing device 40 is shown and described in reference [8].

[0072] The stator manufacturing apparatus 10 may also include a conductor end cutting device 42 for cutting conductor ends 34 that are clamped and fixed by clamping and / or fixing devices 40.

[0073] One embodiment of the stator manufacturing apparatus 10 also includes a conductor end welding device 44 for welding conductor ends 34 to be connected to each other to form a coil.

[0074] In addition, the stator manufacturing apparatus 10 may include a device 46 for electrically contacting the coil formed by the hairpin 12 and / or for testing and / or casting the stator 50 formed therefrom.

[0075] Hereinafter, an embodiment of the conductor end forming apparatus 14 of the stator manufacturing apparatus 10, and the conductor end forming process performed therewith, will be described in detail.

[0076] According to Figure 1 In the stator manufacturing apparatus 10 of the illustrated embodiment, in order to manufacture a sample stator 50 as a component, firstly, a laminated iron core having stator slots 20 and slot insulators 24 housed therein is configured as a stator component 18; simultaneously, a conductor in the form of a hairpin 12 is manufactured. Then, as shown... Figure 2 As shown, a conductor in the form of a hairpin 12 is inserted into the stator component 18. Figure 2 The stator component 18 is shown either with the hairpin 12 inserted or in the process of being inserted.

[0077] The side of each hairpin 12 that is inserted into the stator component 18 is referred to as the winding head side 48 or the insertion side. Conversely, the side of the stator 50 opposite to the insertion side is referred to as the torsion side 52. It is characterized by the protruding, stripped conductor ends 34 of the hairpin 12. To create a closed circuit, the conductor ends 34a-34f are connected to each other in a defined manner.

[0078] Typically, in current hairpin stator manufacturing processes, several methods exist to form these conductor end pairs, thereby creating a closed circuit. One option is to individually bring conductor ends 34a-34f radially to a certain diameter. The minimum distance e between conductor ends 34a-34f is defined by the wall thickness of the torsion tool. For example... Figure 3a and 3b As shown, after the torsion process is completed, the conductor ends 34a-34d are moved toward each other by the clamping and fixing device 40 and then welded. The distance e between the conductor ends 34a-34d and the positional tolerances of the individual conductors must be compensated for by subsequent processes. Given the limited installation space, the areas where the conductor ends 34a-34d can be reliably guided toward each other cannot be designed to be arbitrarily large. Therefore, the resulting offset significantly reduces the process stability of the subsequent welding process. Figure 3a and 3bThe diagram illustrates the sequential steps of inserting two pairs of conductor ends 34a, 34b and 34c, 34d to be welded into a clamping and securing device 40 according to a conventional conductor end forming process. In each case, a distance e exists between adjacent conductor ends 34a-34d, and when this pair is to be welded, the distance e must be reduced by the clamping and securing device 40. In unfavorable cases, this can lead to process instability.

[0079] One way to reduce the distance e is to widen at least some of the already “paired” conductor ends 34a-34f. In this case, conductor ends 34a and 34b have been widened radially in pairs during the widening process prior to the torsion process. The subsequent torsion process is characterized by a significantly smaller distance between a pair of conductor ends, thus improving process stability. A pair widening process has also been proposed in reference [3], but only for “conventional” interconnections without layer jumps on the torsion side. A “layer” is defined as all conductor ends on a common diameter. Two distinct sides can be distinguished on the stator 50 itself, namely the torsion side 52 and the winding head side 48.

[0080] To create a closed circuit, conductor ends 34, 34a-34h are connected to each other in a defined manner on the torsion side 52. Typically, the legs of the hairpin 12 are bent in two different, adjacent positions or diameters. For example, the first lead conductor end 34a of the first hairpin is in the outermost position, while its second lead conductor end 34b is inserted from the outside into a second position, offset by several slots. The different positions of the adjacent conductor ends 34 and the resulting pairing result in the establishment of a closed circuit.

[0081] Based on the geometry of the hairpin used—particularly the geometry of the winding head 32 on the winding head side 48—and the pair formed on the torsion side 52, the stator 50 can be divided into two different categories.

[0082] In the first type of stator, Figure 4An example is shown where layer skipping is achieved via so-called “layer pins.” These specific hairpins 12 (“special pins”) establish a connection between two rings 56a-56d, for example, between the first ring 56a and the second ring 56b. A “ring” is defined as two adjacent positions belonging together. Specifically, rings 56a-56d are a wreath-like arrangement of hairpins 12, with the first leg of each hairpin located at one of the adjacent positions, and the other leg of each hairpin located at another of the adjacent positions. As an example, the first position 58a and the second position 58b together form the first ring 56a, while the third position 58c and the fourth position 58d form the second ring 56b. As a result, pairing on the torsional side is limited only between hairpins 12 of rings 56a or 56b, for example, between the first and second positions 58a and 58b, and between the third and fourth positions 58c and 58d, etc. Due to the interconnection via special hairpin geometries, the number of different hairpin types increases, and thus the complexity of the individual winding heads 32 is increased. The characteristic of the resulting conventional pattern, in which there is no direct connection between the rings on the torsional side, is that all conductor ends 34a-34h at one location are on the same diameter, such as... Figure 4 As shown. In total, in the example of a stator with eight conductor segments, each stator slot forms four rings 56a-56d, with their conductor ends located at eight conventional radial positions 58a-58h.

[0083] on the contrary, Figure 5 An example of a second-type stator 50 is shown, in which layer skipping is achieved on the torsion side 52. Compared to the first-type stator, the second-type hairpin stator 50 can typically be constructed from a smaller number of different hairpins 12. The smaller number of different hairpin types reduces the load that must be provided with different winding heads 32.

[0084] like Figure 5 As shown, some conductor ends 34b-34g of the hairpin 12 are bent so that they are away from their actual positions 58a-58h and located at at least one intermediate position 60 between the two rings 56a-56d. At least one intermediate position 60 is in each case between adjacent positions, for example, between positions 58b and 58c of rings 56a and 56b.

[0085] Electrical connections can be established between different rings 56a-56d of the stator 50 by contacting two such conductor ends 34b-34g, at least one of which is located at the intermediate position 60 on the torsion side 52. Compared to the first type of stator previously described, these second type stators 50 have no (or at least a fewer) layer pins.

[0086] As by Figure 5As can be seen by comparing the conductor ends 34b-34g highlighted in the box with the conductor ends 34a-34h arranged to their right along the circumferential direction (which are in the normal positions 58a-58h), all conductor ends 34b-34g connected for layer skipping can be located in the middle position 60, which is slightly offset from the normal positions 58a-58h.

[0087] In some embodiments, the diameters (i.e., radial positions) of the paired conductor ends 34b, 34c at intermediate position 60 differ from the diameters of the individual positions 58a-58h. In a preferred embodiment, the diameter of intermediate position 60 is preferably between the centers of the diameters of the two adjacent positions 58b, 58c involved.

[0088] The simplification of the winding head 32 due to the reduction in the number of different hairpin geometries is compensated here by a more complex torsion side 52. The conductor ends 34b-34g at positions 58b-58g are extended to two different diameters, which previously significantly reduced process stability because only one position could be achieved using the existing torsion tools. Therefore, when using previously known conductor end forming devices, the displacement of the conductor ends 34 to the corresponding diameters must be allocated to the downstream process. For the second type of stator 50, there is currently no known technical solution to improve positioning accuracy and thus process stability. Figure 5 An exemplary winding scheme with layer jumps on the torsion side 52 and a final intermediate position 60 is shown.

[0089] The following describes a conductor end forming method and a conductor end forming apparatus 14, which allows for a flexible manufacturing process for a second-type stator 50, achieving layer jumps by contacting conductor ends 34b-34g at intermediate positions 60. Specifically, the widening and twisting of conductor ends 34a-34h for manufacturing such a stator 50 with layer jumps is achieved through contact on the twist side 52, where a separate winding scheme is predetermined for this layer jump, which is feasible in a process-safe manner. Preferably, for complex torsional variations, a reliable and precisely positioned widening and twisting process should also be established, which significantly contributes to increasing the process stability of subsequent operations.

[0090] Advantageously, a flexible manufacturing process is achieved by combining different widening tools 61-1, 61-2, 61-3, such as a first widening tool 62-1 for individual conductor ends, a second widening tool 61-2 for conductor end pairs, and (if necessary) a third widening tool 61-3 in the form of a combined widening tool for individual conductor ends and conductor end pairs. Therefore, in the preferred embodiment of the conductor end forming process and the conductor end forming apparatus 14, the torsion tool is also adapted and optimized to the given boundary conditions. The process is executed and controlled to reproduce the final orientation of the conductor ends 34a-34h of the stator 50 as accurately as possible through the widening and torsion processes. Challenges arise due to the numerous variations in geometry and the electrical interconnections of the stator 50 in different stator product families. A preferred design of the tools and process sequence used can be flexibly adapted to existing workpieces, provided that the process stability and at least neutral cycle time are improved relative to previous conductor end forming processes.

[0091] The preferred embodiments of the conductor end forming process and the conductor end forming apparatus 14 are explained in more detail below with reference to the accompanying drawings. The conductor end forming process can be performed by means of the conductor end forming apparatus 14, which is configured to perform the conductor end forming process.

[0092] The conductor end forming method is used to form conductor ends 34a-34h, which extend from the arrangement of stator slots 20 of stator component 18 extending annularly around the central axis.

[0093] The conductor end forming method includes the following steps: a) The conductor ends 34a-34h are widened by means of a plurality of widening tools 61-1, 61-2, 61-3 (such as grippers 62-1, 62-2, 62-3) of the radial bending device 36, such that the widening results in a first portion of the conductor end 34b being located at a first radial position 58b and a second portion of the conductor end 34c being located at a second radial position 58c.

[0094] Step a) includes the following steps: a1) Engaging at least one individual conductor end by at least a first widening tool 61-1, such as a first gripper 62-1, to bend the individually engaged at least one individual conductor end in the radial direction, and jointly clamping at least a pair of radially adjacent conductor ends 34e, 34f by at least a second widening tool 61-2, such as a second gripper 62-2, to jointly bend the pair of radially adjacent conductor ends in the radial direction, wherein step a1) is performed such that a third portion of conductor end 34e is located at at least one intermediate radial position 60 between a first radial position 58b and a second radial position 58c.

[0095] like Figure 5 As shown, the radially inner conductor end 34b of the radially outermost first ring 56a is located in the "conventional" radial second position 58b (second position viewed from the outside), while the radially outer conductor end 34c of the radially outer second ring 56b is located in the conventional radial third position 58c (third position viewed from the outside). The widening process can be performed more flexibly by using different widening tools 61-1, 61-2, 61-3 (e.g., grippers 62-1, 62-2, 62-3) or other widening tools known in principle, for example, from the aforementioned references [9] to

[11] and correspondingly adapted to flexible clamping. Widening is performed in such a way that some of the conductor ends 34c (e.g., see Figure 5 The conductor end 34c in the frame and the corresponding conductor end adjacent to it in the counterclockwise direction are located at the middle position 60, as can also be in Figure 5 See below. Figures 6 to 11 A preferred radial bending device 36 having grippers 62-1, 62-2, 62-3 as widening tools 61-1, 61-2, 61-3 is described in more detail.

[0096] In addition, the conductor end forming method includes the following steps: b) The conductor ends 34a-34h are twisted by bending in the circumferential direction using a circumferential bending device 38, which has a first bending unit 64-1 and a second bending unit 64-2. The first bending unit 64-1 is rotatable in a first rotational direction and has a first annular arrangement 66-1 of a receiving bag 68. The second bending unit 64-2 is rotatable concentrically with the first bending unit in a second rotational direction and has a second annular arrangement 66-2 of a receiving bag 68. In particular, the bending units 64-1, 64-2 have torsion crowns 70A-70H for forming the annular arrangements 66-1, 66-2, ... Examples of embodiments of these bending units 64-1, 64-2 with torsion crowns 70A-70H will be referred to below. Figures 12 to 16 Further explanation.

[0097] Step b) includes the following steps: b0) The first and second bending units 64-1 and 64-2 are arranged in such a way that the bending unit located radially outward has a radially inner receiving bag 68i that opens towards the radially inner side, and the bending unit located radially inward has a radially outer receiving bag 68a that opens towards the radially outer side, wherein b0-1) A portion of the receiving bags 68a, 68i of the first arrangement is located at the first radial position 58b, while another portion of the receiving bags 68a, 68i of the first arrangement 66-1 is radially offset to and located at at least one intermediate radial position 60 and / or b0-2) A portion of the receiving bags 68a, 68i of the second arrangement 66-2 is located at the second radial position 58c, while another portion of the receiving bags 68a, 68i of the second arrangement 66-2 is radially offset to and located at at least one radial intermediate position 60 or another of the plurality of radial intermediate positions 60.

[0098] In addition, step b) includes the following steps: b1) Insert the first portion of the conductor end that was widened to the first radial position 58b in step a) into the first arrangement 66-1 of the receiving bags 68a, 68i, and insert the second portion of the conductor end that was widened to the second radial position 58c in step a) into the second arrangement 66-2 of the receiving bag.

[0099] Step b1) includes: b1a) Insert the conductor end, widened to at least one intermediate radial position 60, into the receiving bag 68a, 68i of another part of the first or second arrangement 66-1, 66-2, and insert the radial inner conductor end of each pair of conductor ends bent together in step a1) into one of the radial outer receiving bags 68a, and insert the radial outer conductor end of the pair of conductor ends into one of the radial inner receiving bags 68i.

[0100] Finally, step b) includes: b2) Rotate the first and second bending units 64-1 and 64-2 relative to each other to bend the first part of the conductor end and the second part of the conductor end in opposite circumferential directions.

[0101] Therefore, the conductor end forming device 14 is adapted to form conductor ends 34a-34h that protrude axially from the arrangement of stator slots 20 of the stator component 18 to form the stator 50 of the motor, the stator slots extending circumferentially around a central axis. The conductor end forming device 14 includes a radial bending device 34 for widening conductor ends 34a-34h using a plurality of widening tools 61-1, 61-2, 61-3 (e.g., grippers 62-1, 62-2, 62-3), the grippers being configured to bend conductor ends 34a-34h in the radial direction such that, after bending, a first portion of the conductor end is located at a first radial position 58b, and a second portion of the conductor end is located at a second radial position 58c. Furthermore, the conductor end forming device 14 includes a circumferential bending device 36 for twisting the conductor ends 34a-34f by bending in the circumferential direction. The circumferential bending device 36 includes a first bending unit 64-1 and a second bending unit 66-2. The first bending unit 64-1 is rotatable in a first rotational direction and has a first annular arrangement of receiving bags 68a and 68i. The second bending unit 64-2 is rotatable in a second rotational direction and is concentrically arranged with respect to the second rotational direction, and has a second annular arrangement of receiving bags 68a and 68i. In the first and second bending units 64-1 and 64-2, the bending unit located radially outward has a radially inward receiving bag 68i that opens radially inward. The bending unit located radially inward has a radially outward receiving bag 68a that opens radially outward. In this configuration, a portion of the receiving bags 68a and 68i of the first arrangement is located at a first radial position 58b, and another portion of the receiving bags 68a and 68i of the first arrangement 66-1 is radially offset to and located at at least one intermediate radial position 60. Alternatively or additionally, a portion of the receiving bags 68a and 68i of the second arrangement 66-2 is located at a second radial position 58c, and another portion of the receiving bags 68a and 68i of the second arrangement 66-2 is radially offset to and located at at least one intermediate radial position 60 or another of the plurality of intermediate positions 60.

[0102] Furthermore, the conductor end forming apparatus 14 includes a controller 54 adapted to control the conductor end forming apparatus 14 to... a) The conductor ends 34a-34h are widened by means of a plurality of widening tools 61-1, 61-2, 61-3 (e.g., grippers 62-1, 62-2, 62-3) of the radial bending device 36, bending the conductor ends 34a-34h in the radial direction, such that the widening results in a first portion of the conductor ends 34a-34h being located at a first radial position 58b and a second portion of the conductor ends 34a-38h being located at a second radial position 58c. a1) Engaging at least a single conductor end by at least a first widening tool 61-1 (e.g., a first gripper 62-1) to individually bend the engaged conductor end in the radial direction, and jointly engaging at least a pair of radially adjacent conductor ends by at least a second widening tool 61-2 (e.g., a second gripper 62-2) to jointly bend the pair of radially adjacent conductor ends in the radial direction, wherein the controller 54 is adapted to perform control of the grippers 62-1, 62-2, 62-3 such that the third portion of the conductor ends 38a-38f is located at at least one intermediate radial position 60 between the first radial position 58b and the second radial position 58c. b) The conductor ends 34a-34f are twisted by bending them in the circumferential direction using the circumferential bending device 38, as follows. b1) Insert the first portion of the conductor ends 38a-38f, which were widened to the first radial position 58b in step a), into the first arrangement 66-1 of the receiving bags 68a, 68i; and insert the second portion of the conductor ends 38a-38f, which were widened to the second radial position 58c in step a), into the second arrangement of the receiving bags 68a, 68i. b1a) Insert the conductor end, widened to at least one intermediate radial position 60, into one receiving bag 68a, 68i of each of the other portions of the first or second arrangement 66-1, 66-2, and insert the radially inner conductor ends of each pair, bent together in step a1), into one of the radially outer receiving bags 68a, and insert the radially outer conductor ends of that pair into one of the radially inner receiving bags 68i. b2) Rotate the first and second bending units 64-1 and 64-2 relative to each other to bend the first part of the conductor end and the second part of the conductor end in opposite circumferential directions.

[0103] Therefore, the controller 54 is adapted to control the conductor end forming apparatus 14 to perform the steps of the conductor end forming process. In particular, a computer program is loaded into the controller 54, which has instructions to cause the conductor end forming apparatus 14 to perform the conductor end forming process.

[0104] Therefore, in the conductor end forming process and conductor end forming apparatus 14, the conductor ends 34b-34g have been brought to the corresponding intermediate radial position 60 during the widening process. These conductor ends 34b-34g will be arranged at the intermediate radial position 60 for interconnection, for example, by connecting the two rings 56a / 56b, 56b / 56c, and 56c / 56d on the torsion side 52. For this purpose, some conductor ends are widened individually, while others are widened in pairs. At least one of the bending units 64-1 and 64-2 has a structure 66-1 or 66-2 with receiving grooves 68a and 68i, which have radially inner and radially outer receiving grooves, so that receiving grooves 68a and 68i are also provided at the radial intermediate position 60. A portion of these receiving grooves 68a, 68i is used to receive conductor ends 34a-34h at conventional positions 58a-58h, particularly conductor ends 34a-34h of rings 56a-56d; another portion of these receiving grooves 68a, 68i is used to receive conductor ends 34b-34g that have been widened to at least one intermediate position 60, for example, conductor ends to be connected for position jumps.

[0105] Below, we will refer to Figures 6 to 11 An embodiment of the radial bending device 36 for widening conductor ends 34a-34h is described in more detail. In principle, the radial bending device 36 can be constructed according to the preferred embodiments described and shown in references [1] and [2], but instead of the same gripper, several different grippers 62-1, 62-2, 62-3 are provided, such as... Figure 6 As shown. Each of the grippers 62-1, 62-2, and 62-3 has first and second grippers 72a and 72b, which are controlled by a controller 54 to move toward each other to clamp conductor ends 34a-34h and to move away from each other to release conductor ends 34a-34h, as shown. Figures 7a to 7b As shown, an example of a first gripper 62-1 designed to clamp a single conductor end 34a is used. Figure 8 The first gripper 72a of the first gripper 62-1 is shown. Figure 9 The first gripper 72a of the second gripper 62-2 is shown. Figure 10 The first gripper 72b of the third gripper is shown. The corresponding second gripper 72b is formed as a mirror image of the first gripper 72a, therefore in Figures 8 to 10 Not shown in the image.

[0106] In addition to the connection hole 74 for fastening, each gripper 62-1, 66-2, 66-3 has a defined gripping area 76 defined by two protruding shoulders 78, 80. The rear shoulder 78 is used to secure the conductor ends 34a-h, and the front shoulder 80 is used to bend the conductor ends 34a-h. See [reference needed]. Figures 7a-7c With the aid of shoulders 78 and 80, one or more conductor ends 34a-34h can be reliably clamped and deformed. The distance between shoulders 78 and 80 is defined by the number of clamped conductor ends 34a-34h.

[0107] Figures 7a-7c An exemplary clamping process for single-pin, single-conductor ends 34a-34h is illustrated. Because the shoulders 80 of the grippers 62-1, 62-2, 62-3, which are away from the central axis of the radial bending device 36, must always engage in the slot region before the conductor ends 34a-34h to be clamped, a minimum wide spacing must be provided between each conductor end 34a-34h in the corresponding stator slot 20. This wide spacing ultimately translates to the design of the torsion tool, whose receiving grooves 86a, 86i require a spacing that defines each other.

[0108] To better position the conductor ends 34a-34h relative to each other, they can also be clamped and widened in pairs. For this purpose, a gripper with a larger gripping area 76, the so-called "dual gripper," is used as a second gripper 62-2. Their gripping areas 76 are designed so that two or more conductor ends 34a-34h can be clamped simultaneously, see [reference needed]. Figure 9 Therefore, there is no wide gap between the conductor ends 34a-34h of the pair of conductor ends.

[0109] However, during the widening process, not all conductor ends 34a-34h are directly widened in pairs. Therefore, pairing may not be completed until the subsequent torsion process, in which two adjacent positions 58a / 58b, 58b / 58c, 58c / 58d, 58d / 58e, 58e / 58f, 58f / 58g, and 58g / 58h rotate relative to each other. This can be seen from... Figures 7a-7c An example of a single grip is obtained from the flowchart. For this purpose, a single gripper is used as the first gripper 62-1. Their gripping area 76 provides only enough space for a single conductor end 34a-34h, see [link to flowchart]. Figures 7a-7c and Figure 8 .

[0110] Furthermore, some of the conductor ends 34a-34h extending from the stator slot 20 may need to be clamped in pairs, and other conductor ends 34a-34h extending from the same stator slot 20 may need to be clamped individually and radially widened. For this purpose, a combined gripper is used as a third gripper 62-3, whose gripping area 76 is preferably axially divided into at least two gripping segments 82-1, 82-2, see [reference needed] Figure 10 In the above Figure 10In the first gripping section 82-1 shown, two conductors can be simultaneously fixed and widened, as in the case of a dual gripper. Their conductor ends extend into the third gripper 62-3, but not far into the second, offset gripping section 82-2. Here, the clamping profile narrows, leaving space only for one conductor end. The insertion depth can be set by the controller 54, as... Figure 10 As indicated by the double arrow 83 in the diagram, and the radial position of the third gripper 62-3, it is possible to ensure that one or both conductor ends 34a-34h are widened simultaneously.

[0111] The use of single, double, or combined grippers—first to third grippers 62-1, 66-2, 66-3—depends on the design of the torsion side 52 and can vary for each (type) of stator 50. All types of grippers 62-1, 62-2, 62-3 can be used in combination around the circumference.

[0112] In other embodiments of the radial bending device 36, not shown in detail here, other correspondingly modified widening tools 61-1, 61-2, 61-3 are used instead of the gripper. Combinations of different types of widening tools are also possible.

[0113] Table 1 below shows exemplary structures of the stator 50 interconnects after widening (upper part of the table) and after torsion (lower part of the table). The final result of the widening process forms the basis for the subsequent torsion process. The final position of the latter can be derived from the displacement of the conductor ends 34a-34h at positions 58a-58h by a defined clockwise or counterclockwise angle. Typically, a multiple of the distance between the two stator slots 20 is chosen as the torsion angle.

[0114]

[0115] At the top of the table, exemplary conductor end positions of the widened first to 36th stator slots 20 (shown as numbers 1-36 in the third row) are shown. Twelve grippers are provided, each for widening the conductor ends 34a-34h of three adjacent stator slots 20. The first row indicates grippers 1 to 12, and the second row indicates their type (1 = single gripper, i.e., first gripper 62-1; 2 = dual grippers, i.e., second gripper 62-2; 3 = combined grippers, i.e., third gripper 62-3). For each position A to H, a distinction is made between external (upper row of positions) and internal (lower row of positions) positions. The position of the conductor end corresponds to the position of each individual conductor end and is important for the subsequent design of the correspondingly adapted torsion crowns 70A-70H. Depending on the position, an inner groove 86i for forming the inner receiving bag 68i or an outer groove 86a for forming the outer receiving bag 68A is provided on the relevant torsion crown, which will be referred to below. Figure 12 and Figure 13 Further explanation: In this example, only all conductor ends of the outermost crown 70A are widened to a single diameter.

[0116] During the widening process, the movement of each gripper 62-1, 66-2, 66-3 (a total of twelve grippers) is individually controlled by the controller 54 based on a set of pre-stored parameters (control dataset). The conductor ends 34a-34h of the twelve stator slots 20 can thus be widened simultaneously; when all conductor ends 34a-34h of these twelve stator slots 20 have been widened, the stator component 18 rotates relative to the radial bending device 36 by an angle corresponding to the stator slot spacing, so as to widen the conductor ends 34a-34h of the next set of twelve stator slots 20 by the twelve grippers 62-1, 62-2, 62-3. This is repeated until all conductor ends 34a-34h of all 36 stator slots 20 have been widened. According to the design, the relative rotation of the stator component 18 and the radial bending device 36 can be performed by rotating the stator component 18 when the radial bending device 36 is stationary, or by rotating the radial bending device 36 when the stator component 18 is stationary, or by a combination of rotating the stator component 18 and the radial bending device 36.

[0117] Compared to previous methods specifically used for the first type of stator, in the embodiment shown in the table, it is no longer possible to widen all conductor ends 34a-34h at positions A to H (58a-58h) to the same diameter. The mapping of the final positions of the conductor ends of the stator 50 and the widening process for its conductor ends require highly flexible conductor end widening processes that can be individually parameterized. Therefore, for all stator slots 20, even within positions A to H, a set of parameters is stored for each conductor end 34a-34h, which ultimately determines the radial position of the conductor ends 34a-34h. This ensures that the conductor ends 34a-34h can always be inserted into the outer groove 86a or inner groove 86i of the torsion crowns 70A-70H provided for them.

[0118] By introducing a so-called master control dataset, the increased parameterization work can be constructed and simplified. Widening operations for multiple conductor ends 34a-34h at positions 58a-58h with the same diameter can be combined into a single master widening operation in terms of control technology. This master widening operation reduces the number of variations in conductor end positions. Thus, each assigned conductor end 34a-34h widening operation is sub-connected to the master control dataset (parameter set) of the stored master widening operation. Which parameters for each conductor end will be handled by the corresponding master widening operation can be flexibly defined. Attributes such as the gripper number and the number of the slot to be processed can also be specifically parameterized.

[0119] If we examine the exemplary widening schemes shown earlier, we can see that different widening processes are required for each stator slot. Depending on position AH, conductor ends 34a-34h are widened during the subsequent torsion process, either by clamping them directly together or individually. For example, only a single widening process is performed for stator slots 4-9, 13-15, or 22-24, while purely paired clamping is used for stator slots 1-3 or 19-21. The type of clamping and widening process can be obtained from the numbers 1 to 3 in the second row (below the labels for grippers 1 to 12 in the first row). Number 1 represents a purely single clamping – the first gripper 62-1 is used for this purpose. Number 2 represents a fully paired clamping, the second gripper 62-2 is used for this purpose. Slots 10-12 and 16-18 are special cases where both individual conductor ends and paired conductor ends must be widened in the radial direction. Here, the number 3 indicates the use of the combined gripper - the third gripper 62-3.

[0120] Different clamping sequences can be distinguished based on the specific conductor end position of each stator slot and the selected gripper type 62-1, 62-2, 62-3.

[0121] Four exemplary widening sequences in Figure 11 The diagram shows the widening sequences WSa) to WSd) each illustrating the widening sequence of eight conductor ends extending from the stator slot 20, where in this case, number 1 represents a specific conductor end (see columns 10-18, 22-24, and 34-36), and numbers 2 to 9 represent conductor ends to be widened to positions H to A (which are to be twisted by the crown H to A), letter A represents the outer row of the corresponding position H to A, and letter i represents the inner row of the corresponding position H to A. Widening sequences WSa) and WSb) are performed by individually widening each conductor end 34a-34h using the first gripper 62-1 (single gripper). For the widening process of a single pin, the inner end position (widening sequence WSa) and the outer end position (widening sequence WSb) can also be distinguished. In widening sequence WSc), conductor ends 34a-34h are widened in pairs using the second gripper 62-2. In the widening sequence (WSd), the third gripper 62-3 is used to widen the conductor ends 34a-34h in combination, either individually or in pairs.

[0122] After the conductor ends have been radially widened, they are then twisted against each other during the torsion process. This is accomplished by the circumferential bending device 38.

[0123] The basic design of the circumferential bending device 38 is as known in references [1] to [5]. The bending units 64-1 and 64-2 are designed with torsion crowns 70A-70H, respectively suitable for the winding scheme of the stator 50 and the resulting pattern of the conductor ends 34a-34h to be connected (see, for example, see...). Figure 5 (or as shown in the table above). The torsion crowns 70A-70H have annular arrangements 66-1, 66-2 of receiving bags 68a, 68i at their free ends. In one embodiment of the circumferential bending device 38, all the more inner torsion crowns 70B to 70H have an inner receiving bag 68i and an outer receiving bag 68a, as shown in the table above. Figure 12 The exemplary torsion crown 70B is shown in the reference section. In the exemplary embodiment shown here, the conductor end 34a (other than a special conductor end) at the outermost position A, 58a is located on the diameter such that the outer torsion crown A has only an inner groove 86i. Some of the conductor ends at the outermost positions may be special conductor ends, for example for interconnecting coil windings, and are specifically torsioned by a separate torsion crown A.

[0124] Each of the torsion crowns 70B-70H has an annular wall 84, with receiving bags 66-1, 66-2 arranged at the axial free end of the annular wall 84. The radially inner receiving bag 68a is formed by an inner groove 86i that is formed radially inward and opens at the axial end. The radially outer receiving bag 68a is formed by an outer groove 86a that is formed radially outward and opens at the axial end.

[0125] To achieve the torsion, the widened conductor end of the hairpin 12 is inserted into the corresponding grooves 86a, 86i of the torsion crowns 70A-70H. As can be seen from the table above, each position A to H thus rotates clockwise or counterclockwise by a certain rotation angle about its central axis. In addition to the rotational movement of the torsion crowns 70A-70H, the stator component 18, or the torsion crowns 70A-70H, axially follow or move toward each other, because the torsion movement results in a shortening of the conductor end length. The torsion crowns 70A-70H have circumferentially distributed grooves 86a, 86i for receiving conductor ends 34a-34h. Due to the nested structure of several such torsion crowns, each groove 86a, 86i of the torsion crowns 70A-70H is closed outward and inward by the corresponding next torsion crown 70A-70H. Furthermore, for the innermost or outermost torsion crowns 70A, 70H, a ring can be used as a closing profile. The grooves 86a and 86i of the torsion crowns 70A-70H are alternately distributed on the entire circumference of the torsion crowns 70A-70H. Each torsion crown 70A-70H may have an inner groove and an outer groove 86i and 86a, the positions of which are particularly suitable for the stator 50 to be processed. Figure 12 and 13 An exemplary torsion crown 70B with an inner groove 86i and an outer groove 86a is shown.

[0126] The distribution of grooves 86a and 86i on the torsion crowns 70A-70H depends on the previously performed widening process. In the above description of the widening process, two distinct positions a and i for each location are discussed. For the conductor end at the outer position a, the associated torsion tool 70A-70H is endowed with an outwardly opening outer groove 86a, and for the inner layer, an inner groove 86i is correspondingly endowed. Each conductor end of the stator 50 has its own torsion crown grooves 86a and 86i.

[0127] This is Figure 14 The example using the torsion crown 70B is shown, with only one inner groove 86i and one outer groove 86a shown for illustrative purposes. Solid lines show the conductor ends 34b inserted into the inner groove 86i and the outer groove 86a. The radial positions of these conductor ends 34b before widening are shown by dashed lines.

[0128] The position of conductor end 34b is determined by the timing of the opening during the widening operation. In order to move the grippers 62-1, 62-2, and 62-3 in the radial direction while holding the conductor end, the position in which the conductor end should be located is defined; relatedly, the time when the grippers 62-1, 62-2, and 62-3 should release the conductor end is defined.

[0129] During the widening motion, the release of the conductor end can be performed with or without a stop.

[0130] Upon reaching the defined stop, the shaft (i.e., the movement actuator of the corresponding gripper) briefly stops at the planned internal target position, grippers 62-1, 62-2, and 62-3 open, and the ends of the conductor are released. Since the widening process typically proceeds from the inside out, the internal position is reached first.

[0131] Conversely, the shaft does not stop when the conductor end is released during the so-called "running" movement. Here, the conductor end is released upon reaching a defined position during the movement of widening the shaft.

[0132] The initial positions of the grooves 86a and 86i in the twisted crowns 70A-70H before twisting correspond to the final positions of the conductor ends after widening (see, for example, the upper part of the table above). Figure 14 The position of the conductor end reflects the final switching scheme of the stator after the torsion. Therefore, the arrangement of the grooves 86a and 86i of each torsion crown 70A-70H also follows the electrical wiring scheme of the stator 50, so that the mating conductor ends are interconnected.

[0133] An exemplary wiring diagram is shown at the bottom of the table above, along with the final result of the twisting operation. During the twisting process, the twisting tool—here, the twisting crowns 70A-70H—rotates clockwise or counterclockwise by a defined angle, in this case by three groove distances (see arrow direction). If the conductor ends are still separated from each other by the six grooves at the start of the widening process, they subsequently form a pair after circumferential twisting in opposite directions. The formation of two exemplary pairs can be seen from the arrows in the table above. The arrows indicate the movement of the conductor ends during the twisting process. Based on the position of the conductor ends, as described above, it can be determined which receiving pockets 68a, 68i—one groove 86a, 86i—of the twisting crowns 70A-70H will subsequently be inserted.

[0134] exist Figure 14 The principle of the inner position i of the inner groove 86i and the outer position a of the outer groove 86a is illustrated again. During widening, the inner radial position i of the inner groove 86i of the corresponding torsion crown 70B is reached first, here for example using the first gripper 62-1. As can be clearly seen, the difference between the two positions a, i lies in the position of the annular wall 84 of the torsion crown 70B. This ultimately determines in which direction (outer or inner) the formation of the pair occurs. For a pure single groove crown, the spacing between the relevant conductor ends is always a distance of at least one wall thickness. However, due to the principle of the inner receiving pocket 68i and the outer receiving pocket 68a formed by the inner groove 86i and the outer groove 86a, smaller radial offsets between the widened conductor ends 34b can also be handled, and even more of this offset at the conductor end at the intermediate position 60 compared to the conductor ends at the conventional positions 58c, 58d can be handled. Here, based on the circuit diagram and stator 50, it is possible to pre-select whether the internal receiving bag 68i or the external receiving bag of each bending unit 64-1, 64-2 is located in a radial position or in an intermediate position, which are among the conventional positions.

[0135] By combining the different radial positions i and a of the inner groove 86i and outer groove 86a on the torsion crowns 70A-70H, the conductor ends 34a-34h to be interconnected can be placed as close to each other as possible. Using the described process and corresponding tools, even stators 50 with position jumps on the torsion side can be rapidly and reliably manufactured in large batches.

[0136] Figure 15 and Figure 16 An exemplary torsion process is shown for the torsion crowns 70A-70C for alternating grooves and the resulting conductor end pairs. Figure 15 The positions of the conductor ends of the two conductor end pairs to be formed before twisting are shown; Figure 16 The position after twisting is shown.

[0137] Since the outermost bending units 64-1 have radially inwardly opening inner grooves 86i, and the innermost bending units 64-2 have radially outwardly opening outer grooves 86a, by aligning the inner grooves 86i and the outer grooves 86a, paired conductor ends that are close to each other can be formed. For example, Figure 16 One of the conductor end pairs shown, such as the one shown in the upper left corner, is used to connect two hairpins in the same ring 56a, while the other conductor end pair, such as the one shown in the center, can be used to electrically connect rings 56a and 56b, wherein at least one of the conductor ends of the conductor end pair is located at at least one intermediate position 60.

[0138] If the conductor ends are widened in pairs using the second gripper 62-1 or the third gripper 62-3 in step a), then the widened pair of conductor ends with corresponding small intervals are introduced into the receiving grooves 68a, 68i of the adjacent torsion crowns 70A, 70B, 70C for torsion. The receiving grooves are initially open to each other and aligned with each other. Figure 16 In principle (although for the final state) as shown. The radially inner conductor end of a pair of conductors is inserted into the outer groove 86a of the radially inner torsion crown 70C; and the radially outer conductor ends of the pair of conductors are inserted into the corresponding aligned inner groove 86i of the radially outer torsion crown 70B. The torsion crowns 70A-70C are then rotated, for example, to form a new pair of conductor ends to be welded together. Alternatively, the individual conductor ends can be retained after setup and then used for external connections of the coil.

[0139] Although the conductor end forming apparatus 14 has been described using the example of manufacturing a second type of stator 50, it is clear that the same conductor end forming apparatus 14 can also be used to manufacture a first type of stator simply by modifying the parameterization of the widening operation and selecting appropriate torsion crowns 70A-70H. Therefore, a very flexible manufacturing process is feasible for very different stators 50.

[0140] Therefore, in order to manufacture very different hairpin-type stators 50 with greater flexibility and process safety, a conductor end forming method and a conductor end forming apparatus 14 have been described. Using this method and apparatus, the conductor ends 34a-34h of the hairpin 12 protruding from the stator slot 20 are formed for forming coil windings. In this process, the conductor ends (34a-34h) are formed in the radial direction by means of different widening tools (61-1, 61-2, 61-3), such as grippers (62-1, 62-2, 62-3), which allow for individual or paired clamping such that a first portion is located at a first radial position 58b, a second portion at a second radial position 58c, and a third portion at at least one intermediate position 60 therebetween. Next, conductor ends 34A-34H are shaped in the circumferential direction using twisting tools 64-1, 64-2; 70A-70H, wherein the outermost twisting tool has an inwardly opening inner receiving pocket 68a and the innermost twisting tool has an outwardly opening outer receiving pocket 68i. In a preferred embodiment, at least one twisting tool 64-1, 64-2; 70A-70H has inner and outer receiving pockets 68a, 68i. A set of these inner and outer receiving pockets is located at at least one intermediate position to shape the third portion of the conductor end.

[0141] List of reference numerals in the attached diagram: 10 stator manufacturing equipment 12 hairpins 14 Conductor end forming device 16-Laminated Iron Core Forming Device 18 stator components 20 stator slots 22-slot insulation fabrication device 24 slot insulation 26 Hairpin Manufacturing Device 28 Pre-positioning devices 30 hair clip insertion device 32 winding head 34 conductor ends 34a First conductor end 34b Second conductor end 34c third conductor end 34d fourth conductor end 34e Fifth conductor end 34f Sixth Conductor End 34g Seventh Conductor End 34h Eighth conductor end 36 Radial Bending Device 38 Circumferential Bending Device 40 Clamping and / or fixing devices 42 Conductor end cutting device 44 Conductor end welding device 46. ​​Apparatus for electrical contact and / or testing and / or casting 48 winding head side 50 stator 52 Torsional side 54 controller 56a First Ring 56b Second Ring 56c second ring 56d Fourth Ring 58a First Position 58b second position 58c third position 58d fourth position 58e Fifth Position 58f sixth position 58g, seventh position 58h, eighth position 60 Middle Position 61-1 First Widening Tool 61-2 Second Widening Tool 61-3 Third Widening Tool 62-1 First Gripper 62-2 Second Gripper 62-3 Third Gripper 64-1 First Bending Unit 64-2 Second Bending Unit 66-1 First Circular Arrangement of Receiving Bag The second annular arrangement of the 66-2 receiving bag 68a Radial External Receiving Bag 68i radial internal receiving bag Torsional crown at positions 58a-58h, 70A-70H 72a First Gripper 72b Second Gripper 74 connecting holes 76 areas of arrest 78 Back shoulder 80 front shoulder 82-1 First Grasp Section 82-2 Second Grab Section 83: Adjustable immersion depth 84 Annular Wall 86a external groove 86i recess e. Distance between the conductor ends to be welded

Claims

1. A method for forming conductor ends to form a stator (50) of an electric motor, said conductor end extending axially from an arrangement of stator slots (20) of a stator component (18) extending annularly around a central axis, said method comprising: a) The conductor end is widened by bending it radially in the radial direction using a plurality of widening tools of a radial bending device (36), such widening causing a first portion of the conductor end to be located at a first radial position (58b) and a second portion of the conductor end to be located at a second radial position (58c); and b) Twisting the conductor end by bending it in a circumferential direction using a circumferential bending device (38), the circumferential bending device (38) having a first bending unit (64-1) and a second bending unit (64-2), the first bending unit (64-1) being rotatable in a first rotational direction and having a first annular arrangement (66-1) of a receiving bag, the second bending unit (64-2) being rotatable in a second rotational direction and concentrically arranged relative to the first bending unit (64-1) and having a second annular arrangement (66-2) of a receiving bag, wherein step b) includes: b1) Insert the first portion of the conductor end, widened to the first radial position (58b) in step a), into the first annular arrangement (66-1) of the receiving bag; insert the second portion of the conductor end, widened to the second radial position (58c) in step a), into the second annular arrangement (66-2) of the receiving bag; and b2) Rotate the first bending unit (64-1) and the second bending unit (64-2) relative to each other to bend the first portion and the second portion of the conductor end in opposite circumferential directions. The characteristic is that step a) includes: a1) Joining at least one single conductor end with at least a first widening tool (61-1) to individually bend the joined at least one single conductor end in the radial direction, and joining at least one pair of radially adjacent conductor ends with at least a second widening tool (61-2) to jointly bend the pair of radially adjacent conductor ends in the radial direction, wherein step a1) is performed such that a third portion of the conductor end is located at at least one radial intermediate position (60) between a first radial position (58b) and a second radial position (58c). The characteristic is that step b) includes: b0) Provides the first bending unit (64-1) and the second bending unit (64-2) such that the first bending unit (64-1) located radially outward has a radially inner receiving bag (68i) opening radially inward, and the second bending unit (64-2) located radially inward has a radially outer receiving bag (68a) opening radially outward, at least one of the first bending unit (64-1) and the second bending unit (64-2) of the circumferential bending device (38) has a torsion crown, the radially inner receiving bag (68i) opening radially inward and the radially inner bending unit (64-2) opening radially inward... The unit has a radially outer receiving bag (68a) with a radially outward opening formed on the torsion crown, wherein a portion of the receiving bag of the first annular arrangement (66-1) is located at the first radial position (58b), and another portion of the receiving bag of the first annular arrangement (66-1) is radially offset to and located at the radial intermediate position (60), and / or a portion of the receiving bag of the second annular arrangement (66-2) is located at the second radial position (58c), and another portion of the receiving bag of the second annular arrangement (66-2) is radially offset to and located at the radial intermediate position (60), and Step b1) includes: b1a) Insert the conductor end widened to the at least one radial intermediate position (60) into another part of the receiving bag of the first annular arrangement (66-1) or the receiving bag of the second annular arrangement (66-2), and insert the radial inner conductor end of each pair of conductor ends bent together in step a1) into one of the radial outer receiving bags (68a), and insert the radial outer conductor end of each pair of conductor ends into one of the radial inner receiving bags (68i).

2. The conductor end forming method according to claim 1, characterized in that, Step a) includes at least one of the following steps: a0) Provides a separate radial bending control dataset for each individual conductor end to be radially bent or for each pair of conductor ends to be bent together, and controls the corresponding widening tool individually by means of the radial bending control dataset assigned to the conductor ends to be bent. a2) Simultaneously using different widening tools in a widening tool set, the widening tool set including a single widening tool for joining a single conductor end, a conductor end pair widening tool for joining a pair of conductor ends, and a combined widening tool formed at different joining portions for joining a single conductor end and for joining a pair of conductor ends; a2a) Simultaneously using different grippers from a gripper group as widening tools, the gripper group including a single gripper for gripping a single conductor end, a pair of conductor end grippers for gripping a pair of conductor ends, and a combined gripper formed at different gripping segments, the combined gripper being used for gripping a single conductor end and for gripping a pair of conductor ends. a3) The widening tool simultaneously engages multiple conductor ends extending from the stator slot (20) at the same radial position, and releases the engaged single or paired conductor ends after a differential movement in the radial direction, so as to bend the first portion to the first radial position (58b), the third portion to at least one radial intermediate position (60), and the second portion to the second radial position (58c).

3. The conductor end forming method according to claim 2, characterized in that, Step a0) includes at least one of the following steps: a0a) Generate a radial bending control dataset based on the winding scheme required for the stator (50) to be manufactured; a0b) Generate a master control dataset for a group or pair of conductor ends or conductor ends to bend equally to the conductor ends, and generate an additional control dataset for a group or pair of conductor ends to bend equally while copying the master control dataset. a0c) parameterization is used for the target position and radial bending motion of each conductor end to generate a radial bending control dataset.

4. The conductor end forming method according to any one of the preceding claims, characterized in that, Step b0) includes at least one of the following steps: b01) Provides a first torsional crown (70B) having an annular wall (84) as a first bending unit (64-1), and forms a first annular arrangement (66-1) of receiving bags at the axial end of the annular wall, wherein the radially inner receiving bag (68i) is formed by an inner groove (86i) formed radially inward and opening at the axial end, and the radially outer receiving bag (68a) is formed by an outer groove (86a) formed radially outward and opening at the axial end; b02) provides a second torsional crown (70C) with an annular wall (84) as a second bending unit (64-2), and forms a second annular arrangement (66-2) of receiving bags at the axial end of the annular wall, wherein the radially inner receiving bag (68i) is formed by an inner groove (86i) formed radially inward and opening at the axial end, and the radially outer receiving bag (68a) is formed by an outer groove (86a) formed radially outward and opening at the axial end.

5. A conductor end forming apparatus (14) for forming conductor ends to form a stator (50) of an electric motor, the conductor ends extending axially from an arrangement of stator slots (20) of a stator component (18) extending annularly around a central axis, the conductor end forming apparatus comprising: A radial bending device (36) for widening the conductor end includes a plurality of widening tools configured to bend the conductor end in the radial direction such that, after bending, a first portion of the conductor end is located at a first radial position (58b) and a second portion of the conductor end is located at a second radial position (58c). A circumferential bending device (38) for twisting the conductor end by bending in a circumferential direction, the circumferential bending device (38) comprising a first bending unit (64-1) and a second bending unit (64-2), the first bending unit (64-1) being rotatable in a first rotational direction and having a first annular arrangement (66-1) of a receiving bag, the second bending unit (64-2) being concentrically arranged with the first bending unit and being rotatable in a second rotational direction and having a second annular arrangement (66-2) of a receiving bag, and Controller (54), adapted to control conductor end forming device (14) to a) The conductor end is widened by bending it radially in the radial direction using the plurality of widening tools of the radial bending device (36), such that the widening results in a first portion of the conductor end being located at a first radial position (58b) and a second portion of the conductor end being located at a second radial position (58c), the radial bending device (36) being able to clamp and engage the conductor end, and b) The conductor end is twisted by bending it in the circumferential direction using a circumferential bending device (38) by means of the following operation: b1) Insert the first portion of the conductor end, widened to the first radial position (58b) in step a), into the first annular arrangement (66-1) of the receiving bag; insert the second portion of the conductor end, widened to the second radial position (58c) in step a), into the second annular arrangement (66-2) of the receiving bag; and b2) Rotate the first bending unit and the second bending unit relative to each other to bend the first portion and the second portion of the conductor end in opposite circumferential directions. The feature is that, in the first bending unit and the second bending unit, the bending unit located radially outward has a radially inner receiving bag (68i) opening radially inward, and the bending unit located radially inward has a radially outer receiving bag (68a) opening radially outward; at least one of the first bending unit (64-1) and the second bending unit (64-2) of the circumferential bending device (38) has a torsion crown; the radially inner receiving bag (68i) opening radially inward and the radially outer receiving bag (68a) opening radially outward... 8a) Formed on the torsion crown, wherein a portion of the receiving bag of the first annular arrangement (66-1) is located at the first radial position (58b), and another portion of the receiving bag of the first annular arrangement (66-1) is radially offset to and located at the radial intermediate position (60), and / or a portion of the receiving bag of the second annular arrangement (66-2) is located at the second radial position (58c), and another portion of the receiving bag of the second annular arrangement (66-2) is radially offset to and located at the radial intermediate position (60). The controller (54) is also designed to control the conductor end forming device (14) during the widening process according to step a) to a1) At least one individual conductor end is engaged by at least one first widening tool (61-1) to bend the individually engaged conductor end in the radial direction, and at least one pair of radially adjacent conductor ends are jointly engaged by at least one second widening tool (61-2) to bend the pair of radially adjacent conductor ends in the radial direction, wherein the controller (54) is adapted to perform control of the widening tools such that a third portion of the conductor end is located at at least one radial intermediate position (60) between the first and second radial positions, and The controller (54) is further adapted to control the conductor end forming device (14) during insertion according to step b1), for b1a) The conductor end widened to the at least one radial intermediate position (60) is inserted into the receiving bag of another part of the first or second annular arrangement, and the radial inner conductor end of each pair of conductor ends that are bent together in step a1) is inserted into one of the radial outer receiving bags (68a), and the radial outer conductor end of each pair of conductor ends is inserted into one of the radial inner receiving bags (68i).

6. The conductor end forming apparatus (14) according to claim 5, characterized in that, The controller (54) is adapted to individually control the widening tool of the radial bending device (36) based on a separate dedicated radial bending control dataset for each individual conductor end to be radially bent or for each pair of conductor ends to be bent together.

7. The conductor end forming apparatus (14) according to claim 5, characterized in that the radial bending device (36) 7.1 Includes different widening tools from a widening tool group, said widening tool group including a single widening tool for joining a single conductor end, a conductor end pair widening tool for joining a pair of conductor ends, and combined widening tools formed at different joining portions for joining a single conductor end and for joining a pair of conductor ends; and / or 7.1a includes different grippers in a gripper group as a widening tool, the gripper group including a single gripper for gripping a single conductor end, a conductor end pair gripper for gripping a pair of conductor ends, and a combined gripper formed at different gripping segments for gripping a single conductor end and for gripping a pair of conductor ends; and / or 7.2 Includes a gripper having a first jaw (72a) and a second jaw (72b), the first jaw (72a) and the second jaw (72b) being movable toward each other for gripping and movable away from each other for release, wherein a receiving groove for a conductor end to be gripped is formed between two shoulders on at least one of the jaws, the groove being configured to surround a single conductor end in the case of a single gripper and around a pair of conductor ends in the case of a conductor end facing the gripper; and / or 7.3 includes a combined gripper with different gripping segments, one gripping segment being configured to clamp a single conductor end, and the other gripping segment being configured to clamp a pair of conductor ends.

8. The conductor end forming apparatus (14) according to any one of claims 5 to 7, characterized in that, The controller (54) is also adapted to control the radial bending device (36) to a3) By means of the widening tool, multiple conductor ends extending from the stator slot (20) at the same radial position are simultaneously engaged, and the engaged single or paired conductor ends are released after differential movement in the radial direction, so as to bend the first portion to the first radial position (58b), the third portion to at least one radial intermediate position (60), and the second portion to the second radial position (58c).

9. The conductor end forming apparatus (14) according to any one of claims 5 to 7, characterized in that, The circumferential bending device (38) includes: The first torsional crown (70B) of the first bending unit (64-1) has an annular wall (84) at the axial end of which a first annular arrangement (66-1) of receiving bags is formed, wherein the radially inner receiving bag (68i) is formed by an inner groove (86i) formed radially inward and opening at the axial end, and the radially outer receiving bag (68a) is formed by an outer groove (86a) formed radially outward and opening at the axial end; and / or The second torsional crown (70C) of the second bending unit (64-2) has an annular wall (84) at the axial end of the annular wall, forming a second annular arrangement (66-2) of receiving bags, wherein the radially inner receiving bag (68i) is formed by an inner groove (86i) that is formed radially inward and opens at the axial end, and the radially outer receiving bag (68a) is formed by an outer groove (86a) that is formed radially outward and opens at the axial end.

10. A controller (54) having a memory capable of loading a computer program having instructions that, when the computer program is loaded into the memory, the controller (54) performs the conductor end forming method according to any one of claims 1 to 5.

11. The controller (54) according to claim 10, wherein, The controller (54) is mounted on the conductor end forming device (14) according to any one of claims 6 to 10.

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