EP3987631A1

EP3987631A1 - Method and device for cutting winding elements to length and bending them

Info

Publication number: EP3987631A1
Application number: EP20785684.0A
Authority: EP
Inventors: Felix WIRTH; Jürgen Fleischer; Pier VAI; Fabrizio Giuradei; Federica FORTE
Original assignee: Gehring Technologies GmbH and Co KG
Current assignee: Gehring Technologies GmbH and Co KG
Priority date: 2019-09-12
Filing date: 2020-09-11
Publication date: 2022-04-27
Also published as: US20230198356A1; DE102019124477A1; WO2021048408A1

Abstract

The invention relates to a method and a device (10) for forming hairpin winding elements or similarly shaped winding elements from a conductor piece (12). According to the invention, a conductor piece (12) is continuously formed by a pivoting mechanism (34, 36), said pivoting mechanism adapting the forming process to the desired shape of the winding element by optical control (200) of the conductor piece (12).

Description

Title: METHOD AND DEVICE FOR CUTTING TO LENGTH AND BENDING

OF WINDING SEGMENTS

Description The invention relates to a method for forming, in particular hairpin-like, winding elements. In addition, the invention relates to a device for forming winding elements. In the manufacture of electric motors for traction drives, individual winding elements (plug-in coils, so-called "hairpins") are produced, which are further processed into a stator winding in the further process. In order to achieve a higher efficiency of electrical machines due to the higher degree of filling of the groove, the hairpin

Technology changed from round to rectangular conductor cross-sections. As part of the manufacture of the winding elements, appropriate conductor pieces must be separated from endless material and converted into suitable ones

Winding elements are formed. The winding elements are then introduced into the stator and, after being positioned on the stator, are welded to one another.

A hairpin-shaped winding element, a so-called hairpin (since its shape resembles that of a hairpin), in the context of the present application means a winding element which comprises two parallel legs and a section connecting these two legs, which is in particular arc-shaped. A hairpin can in particular have a U-shaped profile. The connecting section can in particular have a three-dimensional extension, in particular with constant and variable courses of the radii, that is to say be designed in such a way that parts of the connecting section extend out of the plane of the two legs.

In the prior art, the conductor pieces are usually formed into winding elements by one or more different bending stations (2D or 3D bending stations). This allows the conductor pieces to be brought into the shape required for assembly on the stator.

DE 102009 025 988 A1 describes a device for free-form bending of hollow profiles. US 2003/0029 215 A1 describes a bending device for flat wires.

The devices known from the prior art usually require calibration during operation. In other words, the deformation influences or bending moments exerted on the conductor pieces in the course of the forming process are conventionally calibrated in the course of calibration runs by producing a plurality of shaped conductor pieces, with each conductor piece being shaped in the calibration runs usually using an independent one Test procedure (for example, by inserting a plurality of hairpins into a stator core) is measured for its correct deformation and the deformation influences are adapted in accordance with the results of this separately carried out test procedure.

The invention is based on the object of producing winding elements, in particular one

To enable wire specification, i.e. wire length, with different shapes in a cost-effective manner, with as little scrap as possible being produced, especially at the start of production. Furthermore, a product quality that is as constant as possible should be ensured.

The invention achieves the above object by a method for forming, in particular hairpin-like (so-called “hairpin” or plug-in coil), winding elements from conductor pieces according to the features of claim 1. Correspondingly, the method comprises: reshaping a conductor section into an actual shape using a reshaping device which, in particular by means of kinematic changes in position and position, exerts reshaping influences on the conductor section in order to reshape it. In other words, the conductor section is converted from an initial shape into an actual shape by the forming process. The forming process is carried out by means of the forming device. The shaping device exerts shaping influences on the conductor section. The corresponding deformation influences are typically bending moments and torsional moments. In other words, during reshaping, the conductor section is bent and additionally or alternatively twisted in order to convert the workpiece from the initial shape to the actual shape.

Detecting the actual shape of the conductor section by means of a detection device. The detection device determines the three-dimensional extension of the reshaped conductor section, its three-dimensional shape, the actual shape that results from the reshaping. The detection device is typically a device for machine vision, for example a line scanner, a stereoscopic device or some other type of 3D scanning device.

Determination of a deviation between the actual shape and a desired target shape. The recorded or measured actual shape is given a predetermined desired shape, the Target form, compared. This comparison checks whether there is a discrepancy between the actual shape and the target shape. It is therefore checked whether the forming process has converted the conductor section into the desired shape, or whether there is a discrepancy between the shape resulting from the forming process (actual shape) and the desired target shape (target shape).

Adaptation of the forming influences used during forming based on a possibly determined deviation between the actual shape and the target shape. If a discrepancy is found in the comparison mentioned above, the deformation influences are adjusted so that the discrepancy is compensated as far as possible. In other words, an error in the shape achieved (deviation of the actual shape from the target shape) of the line section is compensated for by adapting the deformation influences to the conductor section. For example, the bending moments and torsional moments used to reshape the conductor section are adapted. As a result, the forming process becomes more and more precise, with this process improvement being automated and also being able to take changes in the process conditions into account. A certain operating state (e.g. certain bending and torsional moments) is not set and this is then carried out again and again without adaptation, but the process control is always improved in the direction of the desired target shape in the event of a deviation.

The actual shape can be recorded as a large number of measuring points or curves that define the contour of the conductor section describe. Correspondingly, the desired shape can also be in the form of a set of points that describes the contour of the conductor section.

It can be provided that rotationally symmetrical conductor pieces are reshaped within the scope of the method. According to the invention it is also provided that the conductor piece to be reshaped has a non-rotationally symmetrical cross section (orthogonal to its longitudinal extension).

The adaptation of the deformation influences can take place during the deformation of a conductor section and the further deformation process can be carried out by means of the adapted deformation influences. In this way, a deviation detected at the beginning of the forming process can be taken into account while the forming process is running and the rest of the forming process can be adjusted accordingly. The resulting deformed conductor section can either be classified as scrap (e.g. in the case of major deviations) or, by adapting the deformation influences, can represent a conductor section that can still be used. Even if the conductor section is to be classified as scrap, the process according to the invention still offers an advantage over an adaptation that only takes place when the next conductor section is formed, since the shaping influences are already set correctly at the beginning of the reshaping process of the next conductor section, since, for example, several adjustment cycles the deformation influences could be carried out during the deformation of a single conductor section. The adaptation of the uniform influences can, however, also only take place after the deformation of a first conductor section and a deformation process of a second (later, but not necessarily directly following) conductor section can be carried out by means of the adapted deformation influences. In this way, for example, different deviations at different points in the shape of the conductor section can be taken into account and the deformation influences can be adjusted more precisely. It can be provided, for example, that the first conductor section is reshaped, then "measured" by means of the detection device (acquisition of the actual shape) and the deviation from the target shape is determined while another conductor section is already being reshaped. When the deformation of the further conductor section is completed with the same deformation influences as in the case of the first conductor section, the deformation process of the second conductor section is carried out with the adapted deformation influences. The acquisition of the actual shape and the comparison with the target shape, the determination of the deviation and the adaptation of the deformation influences are preferably carried out within a period of time that is less than the time required to deform a conductor section.

The (adapted) deformation influences that are used when deforming the conductor section can be determined based on a model, whereby the model determines the deformation influences (e.g. exerted bending and torsional moments) depending on the target shape (desired shape) and property parameters ( e.g. bending stiffness) des Pretends ladder section. For example, calculations based on elementary bending theory can be used here. This has the advantage that a predictive approach is pursued which goes beyond a mere reaction in the adaptation and takes into account knowledge about the deformation behavior of the conductor section, so that a more precise and faster adaptation can take place.

The deformation influences that are used when deforming the conductor section can also be adapted proportionally to the determined difference based on a determined difference between the actual shape and the target shape.

In the event of a discrepancy between the actual shape and the target shape, the property parameters of the conductor section on which the model is based can be adjusted in a model adjustment step in such a way that the model is based on the deformation influences exerted (known and therefore fixed) and the adjusted property parameters (more adaptable in this step Parameter) specifies the actual form (known and therefore fixed). In an adapted forming step, the adapted forming influences (parameters that can be adjusted in this step) can be used for further deformation (remainder of the conductor section or the next conductor section) based on the model (relationship between initial shape, deformation influences, property parameters and the target shape) and the adapted property parameters ( known and thus firmly specified) and the target shape (known and thus firmly specified). Initial values for the property parameters used in the model can be determined by using the reshaping device to carry out a test reshaping process with predetermined test reshaping influences on a test conductor piece that has the same property parameters as the conductor pieces to be reshaped later. The test forming influences are typically less complex than those actually used to manufacture a hairpin

Forming influences. Initial values can also be determined by tensile and / or bending tests in a separate test device. For example, a test lead piece can be subjected to a simple bend through a certain angle. For example, a test lead piece can also be subjected to a torsion through a specific angle. Based on the resulting deformation of the test lead piece, initial values for the property parameters can then be derived accordingly. The resulting actual shape (following the test forming process) of the test lead piece is recorded and based on the actual shape of the test lead piece and the test forming influences used, initial values for the property parameters are determined and the model used as a starting point for determining the forming influences. The uniform device can be a free-form bending device which can deform conductor pieces in any three-dimensional manner.

The reshaping of the conductor section can in particular include:

- Passing the conductor section through a guide in a transport direction which corresponds to the longitudinal direction of the conductor section, the guide having an outlet opening, the opening edges of which contact the outside of the conductor section on both sides when the conductor section passes through, from two mutually perpendicular directions;

The conductor section emerging from the guide is passed through a reshaping unit that follows the outlet opening and comprises a reshaping opening, at the edge of which several reshaping sections are arranged, the reshaping sections contacting the outside of the conductor section on both sides from two mutually perpendicular directions; and

Reshaping of the conductor section by moving the conductor through the reshaping opening while at the same time changing the orientation of the reshaping sections relative to the opening edges of the guide, the reshaping sections being pivoted in the course of the reshaping process relative to the opening edges about at least one pivot axis which runs orthogonally to the transport direction and be moved translationally along at least one plane, the normal vector of which is the pivot axis, with the change the orientation of the uniform sections relative to the opening edges of the guide remains unchanged in its relative position with respect to the opening edges during the reshaping of the reshaping section on an inside of an arc to be formed on the conductor. In other words, it is provided that in this type of process control the deforming section, which is arranged on the inside of a bend to be formed, is not moved relative to the guide. The bending thus takes place through a movement of the deforming section opposite the unmoved deformation section.

In this way, by means of the method according to the invention, a particularly stress-free reshaping, which is particularly necessary in the case of insulated conductor pieces, can be carried out. In addition, particularly narrow radii of curvature and, as a result, particularly complex geometries can be implemented as a result. As already explained above, the conductor passes through both the outlet opening and the forming opening in a precisely predetermined orientation, since it is forcibly guided in the outlet opening and the forming opening from the two mutually perpendicular directions due to the respective bilateral contacting of the conductor section. By changing the alignment of the forming opening to the outlet opening by pivoting during the forming process, the conductor is forcibly bent and / or twisted.

By means of the shaping device, the conductor piece is brought into the desired shape, for which purpose the shaping sections or the shaping device are pivoted as a whole. Around To avoid jamming of the conductor section in the forming device and thus undesired malformations or damage to the conductor section, if the forming device is pivoted about the pivot axes oriented orthogonally to the transport direction, the forming device or its forming sections are moved simultaneously with the pivoting in a plane whose normal vector is the Is the swivel axis (compensation of the swivel movement). In other words, on the one hand there is a pivoting or rotation to deform the conductor section and, on the other hand, a translational movement to compensate for the offset arising in the pivot plane as a result of the pivoting movement (offset of the deformation opening in relation to the outlet opening of the guide). Such a translational compensation is not necessary when pivoting about the transport direction.

By maintaining the position of the inner deformation section, the deformation process of the conductor section is promoted, since - seen in the transport direction - the

Opening cross-section of the deformation opening is changed predominantly or completely on the side facing away from the deformation ("curve outside"). The "hole offset" resulting from the pivoting movement is thus largely or completely compensated for. As a result, the forces generated during the forming process are comparatively low. The tendency of the forming device to become jammed is also low. First, the conductor is passed through a guide, the guide having an outlet opening, the opening edges of which contact the outside of the conductor from two mutually perpendicular directions on both sides (in other words from four sides) when the conductor passes through. Due to the two-sided contacting of the conductor from the two mutually perpendicular directions, the conductor is more or less positively guided in the outlet opening. In other words, it passes through the outlet opening in an orientation precisely predetermined by the contact.

A corresponding forced guidance is present in the deformation opening due to the two-sided contacting of the conductor section from the two mutually perpendicular directions. In other words, it passes through the deformation opening in an orientation precisely predetermined by the contact.

Reshaping takes place by moving the conductor section through the reshaping opening while at the same time changing the orientation of the reshaping sections relative to the opening edges of the guide. The forming sections (or in other words the forming device as a whole) are pivoted in the course of the forming process relative to the opening edges about at least one pivot axis that runs orthogonally to the transport direction and moved translationally along at least one plane whose normal vector is the Pivot axis is. The superimposed translation can compensate for the hole offset and the position of the forming opening or its uniform section on the inside of a curvature can be kept constant with respect to the guide or its opening edges.

As already explained above, the conductor piece passes through both the outlet opening and the forming opening in a precisely predetermined orientation, since it is forcibly guided in the outlet opening and the forming opening from the two mutually perpendicular directions due to the respective bilateral contacting of the conductor piece.

According to the invention, there is also a device for forming, in particular hairpin-like, winding elements from a conductor piece, comprising: a guide, the guide having an outlet opening, the opening edges of which are designed and arranged to allow the conductor piece to pass through the

To contact the outlet opening from two mutually perpendicular directions on both sides of its outer side; a deformation unit which is arranged following the outlet opening and comprises a deformation opening, at the edge of which a plurality of deformation sections are arranged, the deformation sections being designed and arranged to surround the conductor piece as it passes through the deformation opening to contact two directions perpendicular to one another on both sides on its outside; wherein the device has at least one first pivoting device and at least one first compensating device, which cooperate with the forming unit in such a way that the forming sections can be pivoted relative to the opening edges about at least one first pivot axis that runs orthogonally to the transport direction and can be moved translationally along at least one plane, whose normal vector is the swivel axis, the device in particular having a second swivel device and a second compensation device (compensates for the offset occurring during swiveling), which interact with the forming unit in such a way that the deforming sections relative to the opening edges about a second pivot axis, which is orthogonal to the The transport direction runs and is different from the first pivot axis, in particular runs orthogonally to this, pivotable and translationally movable along at least one plane, the normal vector of which is the second pivot axis and wherein the device further comprises a pivoting device which cooperates with the forming unit in such a way that the forming sections can be pivoted relative to the opening edges about at least one pivot axis which corresponds to the transport direction, the device further comprising a detection device which is arranged and designed in this way is that she is a The actual shape of the conductor section resulting from the uniform process is detected by means of machine vision when the conductor section has passed the forming unit.

The device can comprise a control device which is designed and set up to specify the shaping influences (pivoting and compensating movements) exerted on the conductor pieces by means of the shaping unit, the control device being further designed and set up to carry out a method according to the embodiments described here and below perform.

The detection device can be set up and arranged to detect the actual shape of a reshaped conductor section when it emerges from the reshaped sections of the reshaping unit or while it emerges from the reshaped sections of the reshaping unit. Such a detection device can make it possible to adapt the deformation influences during the deformation of a conductor section.

The detection device can be set up and arranged to detect the actual shape of a deformed conductor section after the deformation process of the conductor section has been completed.

The method according to the invention is preferably based on a desired shape which has a 3-dimensional extension. The target shape preferably comprises at least in some areas bending radii that change continuously along the course of the conductor section.

In particular, the method according to the invention takes into account the springback properties of the conductor pieces within the framework of the model.

The shaping process of the conductor pieces takes place in particular through a, in particular continuously, changing relative position of two openings to one another, which the

Forcibly guide conductor pieces and through which the conductor pieces are moved, in particular pushed through.

The conductor pieces are preferably formed from a solid material sheathed with insulation material.

The conductor pieces preferably have an essentially rectangular cross section, in particular with rounded corners. In particular, the forming process used within the scope of the method according to the invention is a kinematic bending process with changing bending radii. The desired shape is, in particular, a three-dimensional shape, that is to say a shape that does not run within a plane. In particular, non-constant free-form bending radii are used in the forming process. In particular, the forming process does not take place in a constant bending plane. The invention is described in more detail below with reference to the figures, where the same or functionally identical elements are provided with reference symbols only once if necessary. Show it:

Fig.l shows an embodiment of a device for forming a hairpin-shaped winding element from a conductor section in a perspective front view;

FIG. 2 shows the device from FIG. 1 in a perspective rear view;

3 shows the device from FIG. 1 in a partial and enlarged front view;

4a-c show an embodiment of a shaping device of the device from FIG. 1 in several views;

5a-c show an embodiment of a shaping device of the device from FIG. 1 in several views;

6a-c show an embodiment of a shaping device of the device from FIG. 1 in several views;

7 shows a change in the orientation of the

Deforming sections relative to the opening edges of the guide in a schematic representation;

8 shows a hairpin; 9 shows a possible sequence of the invention

Procedure;

10 shows a possible sequence of the method according to the invention;

FIG. 11 shows a model for carrying out the method according to the invention, with deformation influences being determined; and

FIG. 12 shows the model for carrying out the method according to the invention, with adapted property parameters being determined.

FIG. 1 shows a device 10, which represents a shaping device, for forming, for example, a hairpin-shaped winding element ("hairpin") from a conductor section 12. The conductor section 12 is elongated along a longitudinal direction (X direction) and has a lengthwise direction Outside 13 extending in the longitudinal direction. In the present case, the components of the device 10 are coupled to or attached to a frame 14 serving as a support structure.

The device 10 has a guide 16 (partially covered in FIG. 1) and a shaping unit 18 through which the conductor section 12 is guided. The forming unit 18 can be moved relative to the guide 16 by means of a plurality of pivoting devices and a plurality of compensating devices, as a result of which the conductor section 12 guided through the guide 16 and the forming unit 18 becomes, for example, a. can reshape hairpin-shaped winding element. This is explained in detail below, reference being made to the spatial axes drawn in FIG. 1 (X-axis, Y-axis and Z-axis). The X-axis extends along the longitudinal direction of the conductor section 12, the Y-axis extends orthogonally upwards (in FIG. 1 vertically upwards) and the Z-axis extends orthogonally to the XY-plane (in FIG. 1 obliquely to the left below).

As already indicated, the device 10 has a guide 16 (partially covered in FIG. 1) which has an outlet opening 20 (see FIG. 7). The opening edges 22 of the outlet opening 20 are designed and arranged in order to contact the conductor piece 12 on both sides (from four sides) as it passes through the outlet opening 20 from two directions perpendicular to one another (only indicated in FIG. 7).

As also indicated above, the device 10 has a forming unit 18 which is arranged directly following the outlet opening 20 in the transport direction of the conductor section 12 (X-axis) and comprises a forming opening 24. On the edge or the edges of the deformation opening 24 are arranged four deforming sections 26, which are designed and arranged to surround the conductor section 12 as it passes through the deformation opening 24 from two mutually perpendicular directions on both sides, i.e. from four sides, on its outer side 13 to contact. The four deformation sections 26 are designed and arranged in such a way that the deformation opening 24 is largely rectangular.

The device 10 has at least one pivoting device and at least one compensating device, which interact with the forming unit 18 in such a way that the forming sections 26 can be pivoted relative to the opening edges 22 about at least one pivot axis 28 and can be moved along at least one plane 30, the normal vector of which is the pivot axis 28 (illustrated in Figure 7).

In the exemplary embodiment, the device 10 has a first pivot device 32, a second pivot device 34, a third pivot device 36, a first compensation device 38 and a second compensation device 40.

The first pivoting device 32 has a first, inner suspension 42, to which the forming unit 18 is fastened, for example screwed. The inner suspension 42 is mounted pivotably about a first pivot axis (X-axis) extending along the transport direction of the ladder section 12 and is pivotable by means of a first drive device 44. With this, the conductor section 12 can be reshaped around the transport direction (X-axis) (torsion of the conductor section 12 around the X-axis). Since there is no offset here (central longitudinal axes of outlet opening 20 and deformation opening 24 are congruent or both lie on the X axis), is on the first Pivoting device 32 no compensating device required.

The inner suspension 42 (main disk 42) is disk-shaped and has a recess 43 which is open to the side (circular ring section).

The recess 43 creates space for the deformation of the conductor section 12 (for example in the case of bends through 180 °).

Fastening sections 46 for the forming unit 18 are formed on the inner suspension 42 and have bores or passages with internal threads for screw fastening as fastening points (without reference symbols). The inner suspension 42 is pivotably held by several bearings 48, which are offset by 120 °, for example, in relation to the transport direction (X-axis). These bearings 48 are attached to the central suspension 50 as described below.

The inner suspension 42 has on its outer circumference a radially projecting collar 52 which corresponds to a groove 54 formed in each of the bearings 48. The first drive device 44 can have a motor, for example a (brushless) electric motor, which can drive the inner suspension 42 about its pivot axis (X-axis). The drive device 44 and the inner suspension 42 are coupled by means of a gear connection or a helical gear transmission. The motor shaft of the drive device 44 and the pivot axis (X axis) are oriented parallel to one another. The second pivoting device 34 has a second, middle suspension 50 which is pivotably mounted about a second (here vertical) pivoting axis (Y-axis) that is orthogonal to the transport direction (X-axis) and is pivotable by means of a second drive device 56 (pivoting movement about the Y -Axis). This enables the conductor section to be reshaped in one plane ("2D reshaping", ie reshaping into a flat hairpin).

The inner suspension 42 and the forming unit 18 attached to it are mounted on the central suspension 50. The middle suspension 50 (second disk 50) is disk-shaped and has a recess 58 (flat circular ring section). The recess 58 creates space for the deformation of the conductor section 12. The bearings 48 are each fastened to the central suspension 50 by means of a screw connection. The first drive device 44 for the inner suspension 42 is also attached to the middle disk 50, for example by means of screw connections.

The pivoting movement (rotation) of the central suspension 50 is predetermined directly by the motor shaft (without reference symbols) of the second drive device 56. The second drive device 56 has a motor, for example a (brushless) electric motor, the second pivot axis (Y-axis) and the central longitudinal axis of the motor shaft being congruent. The second drive device 56 is attached to an outer suspension 60, as described below. A fixation of the middle The suspension 50 on the outer suspension 60 takes place by means of bearing units 62, which enable a pivoting movement about the second pivot axis (Y-axis). The bearing units 62 have a plurality of fastening sections 64, bolts 66 and roller bearings (not shown).

The third pivoting device 36 has a third, outer suspension 60, which is pivotably mounted about a third (here vertical) pivoting axis (Z-axis) that is orthogonal to the transport direction and is pivotable by means of a third drive device 68 (pivoting movement about the Z-axis). This enables the conductor section 12 to be deformed in a further plane (“2D deformation”), for example a plane that is vertical with respect to the frame 14 of the device 10 (X-Y plane). Together with the second pivoting device 34, a three-dimensional deformation of the conductor section 12 into a winding element is thus possible (“3-D deformation”).

On the outer suspension 60, the middle suspension 50 and the inner suspension 42 with the forming unit 18 attached thereto are mounted. The outer suspension 60 is designed as a circular ring section and has a C-shaped cross section. The bearing units 62 and the second drive device 56 for the central suspension 50 are fastened to the outer suspension 60.

The pivoting movement (rotation) of the outer suspension 60 is specified directly by the motor shaft (without reference symbols) of the third drive device 68. The third Drive device 68 has a motor, for example a (brushless) electric motor, the third pivot axis (Z-axis) and the central longitudinal axis of the motor shaft of the third drive device 68 being congruent. The third drive device 68 is fastened to the frame 14 by means of the first compensation device 38 and / or the second compensation device 40, as described further below.

The forming unit 18 is designed as an exchangeable tool unit (see FIGS. 4 to 6). In this way, the suitable forming unit 18 can be selected and adapted to the forming.

The forming unit 18 has a plate-shaped holding structure 70 (base plate 70) with bores / passages for attachment to the inner suspension 42. The shaping unit 18 has two adjusting devices 72, 74 for fine adjustment of the shaping unit 18 in the plane of the base plate 70. For this purpose, the shaping unit 18 has stops 76, 78 which can be adjusted relative to the base plate 18. The stop 76, 78 can each be adjusted and fixed relative to the base plate 70 by means of a fixing screw 80. Bores or passages with threads for fastening to the inner suspension 42 can be formed in the stop 76, 78 (without reference symbols). The device 10 can have several different shaping devices 18 or tool units, for example a set of different shaping devices 18 can be held with the device 10. The uniform sections 26 of the forming unit 18 are each formed by a pin 82 or by a roller 84, which can optionally be mounted on the forming unit 18 by means of a roller bearing 86. Due to the rectangular

In the cross-sectional shape of the conductor piece 12, four deforming sections 26 are provided in each case.

To provide a structurally simple forming unit 18, the pins 82 (without roller bearings) can be attached to or in the base plate 70 (see FIG. 5). If the conductor section 12 is passed through the deformation opening 24, the pins 82 do not rotate or only rotate slightly. Structurally higher-quality solutions can be achieved through designs with roller bearings. The pins 82 can be mounted on or in the base plate 70 by means of roller bearings 86 (see FIG. 4a). Likewise, rollers 84 can be mounted on or in the base plate 70 by means of roller bearings 86 (see FIG. 6a). The rollers 84 or the roller bearings 86 can be attached by means of screws 88

Bearing blocks 90 are attached, which are attached to the base plate 70.

As already indicated, the device 10 has a frame 14 as a support structure, the third pivoting device 36 by means of the first compensating device 38 and the second

Compensation device 40 is coupled to frame 14. The first compensation device 38 has a first slide 92 which can be moved along a horizontal direction with respect to the frame 14 and which can be driven by means of a fourth drive device 94 so that the forming unit 18 can be moved along the pivot axis of the third pivot device (Z-axis). As a result, the lateral offset in relation to the conductor section 12 (offset in the Z direction) can be compensated as an effect of the pivoting movement about the Y axis.

The first slide 92 can be coupled to the frame 14 by means of four linear guides 96 (for example with a cage ball). Two linear guides 96 are attached to an upper frame section 14 'and two linear guides 96 are attached to a lower frame section 14 ". The first slide 92 can be moved along the linear guides 96 by the fourth drive device 94. The fourth drive device 96 can have a motor, for example a (brushless) electric motor, and can be fixed on the frame 14. A spindle 98 (ball screw 98) is coupled to the motor shaft and cooperates with a nut (spindle nut; not shown) attached to the first slide 92. The motor shaft of the fourth drive device 96 is coupled to the spindle 98 by means of a metal bellows coupling 100.

The second compensation device 40 has a second slide 102 which can be moved along a vertical direction relative to the frame 14 and which can be driven by means of a fifth drive device 104 so that the Forming unit 18 can be moved along an axis (Y axis) which is orthogonal to the pivot axis of the third pivot device 36 (Z axis). As a result, the vertical offset (offset in the Y direction) in relation to the conductor section 12 as an effect of the pivoting movement about the Z axis can be compensated.

The second slide 102 is coupled to the frame 14 by means of two linear guides 106 (for example with a cage ball). The second slide 102 can be driven along the linear guides 106 by means of the fifth drive device 104. The fifth drive device 104 has a motor, for example a (brushless) electric motor, and is fixed on the frame 14. A spindle 108 (ball screw spindle 108) is coupled to the motor shaft of the fifth drive device 104 and cooperates with a nut (spindle nut; not shown) attached to the second slide 102. The motor shaft is coupled to the spindle 108 by means of a metal bellows coupling 110.

Forming device 10 further comprises a detection device 200 or several

Detection devices 200 which are arranged and designed in such a way that they detect an actual shape of the conductor section 12 resulting from the reshaping process by means of machine vision when the conductor section 12 has passed the reshaping unit 18. The detection device 200 in the sense of the invention is a device for detecting 3-dimensional shape data of the reshaped conductor section 12. The detection device 200 detects the shape preferably by optical means. It can Line scanners, strip light systems or stereoscopic measuring devices can be used.

Forming device 10 further comprises a

Control device 300, which is designed and set up to predetermine the shaping influences exerted on the conductor pieces 12 by means of the shaping unit 18. In other words, the control device 300 controls the forming device 10 and specifies the pivoting positions of the pivot devices 32, 34 and 36 as well as the respective compensation movement by the compensation devices 38 and 40. To this end, the control device 300 controls the respective pivot devices 32, 34 and 36 and compensation devices 38 , 40 assigned

Drive units 44, 56, 68, 94, 96 and 104 on. Connection 310 to the drive units are indicated symbolically in FIG. 1; these can be designed in various ways, for example, wired or wireless.

The method for forming a preferably hairpin-shaped winding element (hairpin; plug-in coil) from a conductor piece 12, which is elongated along a longitudinal direction (X-axis) and has an outer side 13 extending along the longitudinal direction, is based on the example of the use of the forming device 10 , as follows:

Forming a conductor section 12 into an actual shape. In other words, the conductor section 12 is removed from its straight starting shape by means of the reshaping device 10 into an actual shape, which corresponds, for example, to the hairpin shape shown in FIG. 8.

In this case, the shaping device 10 exerts shaping influences on the conductor section 12 in order to reshape it. These deformation influences are brought about by pivoting the deformation unit 18 with respect to the guide 16 or its outlet opening 20. In addition, the translational compensatory movements described above can be present in order to avoid an offset to the guide and the forming unit 18.

Detecting the actual shape of the conductor section 12 by means of the detection device 200. The detection device 200 is able to create a 3-D profile of the conductor section. The actual shape of the conductor section can be measured directly when it emerges from the forming unit 18. It is also conceivable to use a detection device 200 which measures the finished hairpin three-dimensionally and thereby determines its actual shape.

The method further comprises determining a deviation between the actual shape and a desired target shape.

This determination of the deviation can take place over the entire extent of the finished, unformed conductor section 12 or, for example, if a detection device 200 is used that measures the hairpin as soon as it leaves the shaping device 18, also locally or in sections. The method further comprises the adaptation of the shaping influences used during the shaping based on a possibly determined deviation between the actual shape and the target shape. This adaptation can also take place at the end of the complete reshaping of the conductor section into a hairpin or locally or in sections as soon as a deviation from the desired target shape is recognized.

Specifically, in the present example, the conductor section 12 is first passed through the guide 16. The opening edges 22 of the outlet opening 20 contact the outside 13 of the conductor section 12 from two mutually perpendicular directions on both sides (from four sides) when the conductor section 12 passes through.

The conductor section 12 emerging from the guide 16 is guided through the reshaping unit 18 with the reshaping opening 24 following the outlet opening 20 directly (in the transport direction of the conductor section 12). The deformed sections 26 contact the outside 13 of the conductor section 12 from two directions perpendicular to one another on both sides (from four sides).

The reshaping of the conductor section 12 takes place by moving the conductor section 12 through the reshaping opening 24 while at the same time changing the orientation of the reshaping sections 26 relative to the opening edges 22 of the guide 16 or the outlet opening 20 Forming unit 18 as a whole) in the course of the forming process is pivoted about the corresponding pivot axis pivot axis 28 relative to the opening edges 22 and moved along at least one plane 30, the normal vector of which is pivot axis 28.

When changing the orientation of the deformed sections 26 relative to the opening edges 22 of the guide 16, the deformed section 26 on the inside of the arc to be formed on the conductor section 12 (inner radius) is not changed in its relative position with respect to the opening edges 22 of the guide 16, rather it remains in its position Relative position with respect to the opening edges 22. As a result, the "hole offset" resulting from the pivoting movement is practically compensated for.

This aspect is illustrated in FIG. The starting position of the shaping unit 18 or the shaping sections 26 (continuous conductor section 12 would not undergo any shaping) is shown in FIG. 7 with solid lines. A possible reshaping of the reshaping unit 18 or the reshaping sections 26 (continuous conductor section 12 is reshaped as shown) is shown with dashed lines. If the orientation of the forming unit 18 were to take place relative to the opening edges 22 starting from the starting position (solid lines) without compensation of the hole offset, the forming unit 18 would be pivoted about a pivot axis that intersects the conductor section 12, which would result in the Conductor section 12 would be loaded by the uniform sections 26 from two opposite sides (not shown). An offset would arise between the guide 20 and the forming opening 24.

To avoid this, the forming unit 18 is not only pivoted, but also moved in a translatory manner in the pivot plane 30, the normal vector of which is the pivot axis 28, towards the inside of the forming (inner radius) (illustrated by arrow 31). This takes place in such a way that the deforming section 26 'arranged on the inside of the sheet does not change its position relative to the opening edges 22 during the deformation. The superimposed pivoting movement and translatory compensating movement are thus coordinated with one another in such a way that the deforming section 26 ′ does not perform any relative movement when pivoting with respect to the opening edges 22.

By pivoting the deforming sections 26, the conductor section is bent or twisted. The bending or torsional moments exerted represent the deformation influences exerted on the conductor section 12.

The detection device 200 detects the shape of the conductor section when it emerges from the deforming unit 18.

The shape information acquired by the acquisition device 200, the actual shape of the conductor section, is sent to the Control device 300 transmitted. The

Control device 300 carries out a comparison between the shape information acquired by acquisition device 200, the actual shape of the conductor section after the forming process, and the desired target shape. If a deviation is found, the fits

Control device 300 the forming influences. In other words, it changes the pivot position of the deforming sections 26 provided for a specific bend or torsion or changes the bending or torsional moments intended for a specific bend or torsion that are to be exerted on the conductor section 12.

This adaptation of the deformation influences (bending and torsional moments) can take place during the deformation process of a conductor section, so that the rest of the conductor section is processed with the newly determined deformation influences or it can take place after the complete deformation process, so that the next conductor section is exposed to the corrected deformation influences .

FIG. 8 shows a hairpin 140 produced by means of the method according to the invention on the device according to the invention. The hairpin 140 has two parallel, straight legs 150 and a connecting section 160 protruding from the plane of the legs 150 Hairpins 140 exerted on the previously rectilinear conductor section 12. FIG. 9 illustrates a variant of the method according to the invention.

In a step 400, a conductor section 12 is reshaped into an actual shape using a reshaping device 10 which exerts reshaping influences on the conductor section 12 in order to reshape it.

In a step 410, in the present example after the conclusion of step 400, the actual shape of the conductor section 12 is recorded by means of a detection device 200, in particular a detection device 200 for machine vision.

In a step 420, in the present example after the conclusion of step 410, a deviation between the actual shape and a desired target shape is ascertained.

In a step 430, in the present example after the conclusion of step 420, the deformation influences used in the deformation are adapted based on a possibly determined deviation between the actual shape and the target shape. After step 430 has been completed, a further forming process is carried out in a further step 400 with a further conductor section 12.

In the example of FIG. 9, the adaptation of the deformation influences is carried out after the deformation of the entire conductor section 12 has been completed. The The actual shape of the conductor section 12 can be detected either during the deformation or after the end of the deformation.

FIG. 10 illustrates a further variant of the method according to the invention.

In a step 410, in the example of FIG. 10 while step 400 is being carried out, the actual shape of the conductor section 12 is detected by means of a detection device 200, in particular a detection device 200 for machine vision.

In a step 420, in the example of FIG. 10, after step 410 has been completed and while step 400 is being carried out, a deviation between the actual shape and a desired target shape is determined.

In a step 430, after the conclusion of step 420 and while step 400 is being carried out, the deformation influences used in the deformation are adapted based on a possibly determined deviation between the actual shape and the target shape. Steps 410 and 420 are carried out continuously while the reshaping is being carried out, that is to say during step 400. As soon as there is a discrepancy between the actual form and the target Shape is determined locally, the corresponding deformation influences are adapted in step 430, which is then initiated accordingly. After completion of the respective step 430, the conductor section 12 is further deformed, that is to say step 400 is continued. After step 400 has been completed, a further forming process is carried out in a further step 400 with a further conductor section 12.

In the example of FIG. 10, the adaptation of the deformation influences is carried out during the deformation of the conductor section 12. Correspondingly, the actual shape of the conductor section 12 is also recorded during the deformation.

FIGS. 11 and 12 illustrate a model 500 for calculating the deformation influences 540. In order to calculate the deformation influences 540, the model 500 takes into account at least the initial shape 510, the desired target shape 520 and property parameters 530 of the conductor section 12 to be deformed as parameters.

In order to determine the deformation influences 540 for a first deformation process, an estimate or initial values determined in a test run can be used for the property parameters 530.

If a discrepancy 550 is found between the measured actual shape 560 and the desired shape 520, the property parameters 530 are adjusted so that in a further run of the calculation shown in FIG. 11 instead of the initial value for the property parameters 530, adapted property parameters 530 'are used.

The determination of the adapted property parameters 530 'is illustrated in FIG.

The adapted property parameters 530 'are calculated by means of the model, with the model at least the initial shape 510 and the shaping influences 540 exerted in the shaping process (which were previously determined according to FIG. 11) as well as either the originally planned target shape 520 and the determined deviation 550 or the measured actual shape 560 is taken into account.

The model 500 is based on a reversible mathematical relationship between the individual parameters.

The method according to the invention is preferably based on a desired shape which has a 3-dimensional extension. The desired shape preferably includes bending radii that change continuously over the course of the conductor section.

Claims

1. A method for forming, in particular hairpin-like, winding elements from conductor pieces (12), in particular wherein the conductor pieces (12) are elongated in an initial state along a longitudinal direction (X), the method comprising:

Reshaping a conductor section (12) into an actual shape (560) using a reshaping device (10) which exerts reshaping influences (540) on the conductor section (12) in order to reshape it;

Detecting the actual shape (560) of the conductor section (12) by means of a detection device (200), in particular a detection device (200) for machine vision;

Determining a deviation (550) between the actual shape (560) and a desired target shape (520);

Adaptation of the deformation influences (540) used during deformation based on a possibly determined deviation (550) between the actual shape (560) and the desired shape (520).

2. The method according to claim 1, characterized in that the adaptation of the forming influences (540) during the shaping of a conductor section (12) takes place and the further shaping process is carried out by means of the adapted shaping influences (540).

3. The method according to claim 1, characterized in that the adaptation of the deformation influences (540) following the deformation of a first conductor section

(12) takes place and a deformation process of a second conductor section (12) is carried out by means of the adapted deformation influences (540).

4. The method according to any one of the preceding claims, characterized in that the deformation influences (540) that are used when deforming the conductor section (12) are determined based on a model (500), the model (500) depending on the deformation influences of the desired shape (520) and of property parameters (530) of the conductor section (12).

5. The method according to the preceding claim, characterized in that in the event of a discrepancy between the actual shape (560) and the desired shape (520), the property parameters (530) of the conductor section (12) on which the model (500) is based in one

Parameter adaptation step can be adapted in such a way that the model (500) specifies the actual shape (560) based on the applied deformation influences (540) and the adapted property parameters (530), with the adapted deformation influences (540) based on the Model (500) and the adapted property parameters (530 ') as well as the target shape (520) can be specified.

6. The method according to the preceding claim, characterized in that initial values for the property parameters (530) used in the model are determined in that, using the reshaping device (10), a test reshaping process with predetermined test reshaping influences on a test lead piece, the same property parameter (530) how the conductor pieces (12) to be reshaped later is carried out and the resulting actual shape (560) of the test conductor piece is recorded and, based on the actual shape (560) of the test conductor piece and the test shaping influences used, the property parameters (530) are determined and the Model for determining the deformation influences (540) can be used as a starting point.

7. The method according to any one of the preceding claims, characterized in that the forming device (10) is a free-form bending device.

8. The method according to any one of the preceding claims, characterized in that the reshaping of the conductor section (12) comprises:

- Passing the ladder section (12) in a transport direction which corresponds to the longitudinal direction of the (X) of the ladder section, through a guide (16), the guide (16) having an outlet opening (20), the opening edges (22) of which upon passage of the conductor section (12) contacting the outside (13) of the conductor section (12) on both sides from two mutually perpendicular directions;

- Passing the conductor section (12) emerging from the guide (16) through a uniform unit (18) following the outlet opening (20) which comprises a forming opening (24) at the edge of which several forming sections (26) are arranged, the forming sections (26) make contact with the outside (13) of the conductor section (12) on both sides from two mutually perpendicular directions; and

- Reshaping the conductor section (12) by moving the conductor section (12) through the reshaping opening (24) while at the same time changing the orientation of the reshaping sections (26) relative to the opening edges (22) of the guide (16), the reshaping sections (26) in the course of the forming process relative to the opening edges (22) about at least one pivot axis (28, Y, Z), which runs orthogonally to the transport direction, are pivoted and moved translationally along at least one plane (30) whose normal vector defines the pivot axis (28, Y ,

Z), with the change in the orientation of the deformed sections (26) relative to the opening edges (22) of the guide during the deformation (16) of the deformed section (26 ') on an inside of a conductor piece (12) to be trained sheet remains unchanged in its relative position with respect to the opening edges (22).

9. Device (10) for forming, in particular hairpin-like, winding elements from a conductor piece (12), comprising: a guide (16), the guide (16) having an outlet opening (20), the opening edges (22) of which are designed and arranged are to the conductor piece (12) when passing through the

To contact the outlet opening (20) from two mutually perpendicular directions on both sides of its outer side (13); a shaping unit (18) which is arranged following the outlet opening (20) and comprises a shaping opening (24), at the edge of which several shaping sections (26) are arranged, the shaping sections (26) being designed and arranged to surround the conductor piece ( 12) to make contact on both sides of its outer side (13) when passing through the forming opening (24) from two mutually perpendicular directions; wherein the device (10) has at least one pivoting device (34, 36) and at least one

Compensating device (38, 40) which interacts with the forming unit (18) in such a way that the forming sections (26) relative to the opening edges (22) about at least one pivot axis (28, Y, Z), the runs orthogonally to the transport direction (X), are pivotable and translationally movable along at least one plane (30), the normal vector of which is the pivot axis (28, X, Y, Z) and wherein the device (10) has at least one pivot device (32), which cooperates with the forming unit (18) in such a way that the forming sections (26) can be pivoted relative to the opening edges (22) about at least one pivot axis (X) which corresponds to the transport direction, the device (10) also having a detection device (200 ), which is arranged and designed in such a way that it detects an actual shape (560) of the conductor section (12) resulting from the forming process by means of machine vision when the conductor section (12) has passed the forming unit (18).

10. Device (10) according to the preceding claim, characterized in that the device (10) comprises a control device (300) which is designed and set up to predetermine the deformation influences exerted on the conductor pieces (12) by means of the deformation unit (18) , wherein the control device (300) is further designed and set up to carry out a method according to one of claims 1 to 8.

11. The device (10) according to one of the two preceding claims, characterized in that the detection device (200) is set up and arranged to detect the actual shape (560) of a deformed conductor section (12) when it emerges from the deformed sections ( 26) of the forming unit (18) emerges.

12. Device (10) according to one of the two preceding claims, characterized in that the detection device (200) is set up and arranged to detect the actual shape (560) of a reshaped conductor section (12) after the

The forming process of the conductor section (12) is complete.