Apparatus and method for bending wires of machine elements for electric machines

Abstract

To simplify start-up operation and parameter changes in 3D bending of a wire (10), the invention implements a 3D bending device (46) and a 3D bending method for bending a wire (10), wherein the wire (10) is held on a first leg (12) and a second leg (14), and the legs (12, 14) are moved in a first to third relative movement with first to third axes of movement (64, 66, 68) by means of first to third relative movement means (54, 56, 58) in order to change the twist angle (α1, α2) of the first and second legs (12, 14) and the distance (s0, s) between the central axes of the legs (12, 14) in a manner that can be set independently of one another.

Description

Technical Field

[0001] This invention relates to a 3D bending apparatus for bending wire into a three-dimensional shape to manufacture machine components for an electric motor, the wire comprising a first leg, a second leg, and a bent section between the legs. Furthermore, this invention relates to a 3D bending method for bending wire into a three-dimensional shape to manufacture machine components for an electric motor, the wire comprising a first leg, a second leg, and a bent section between the legs. Background Technology

[0002] Such a 3D bending device and such a 3D bending method are known from US 2014 / 0223727A1 and DE 10 2018 108 656 A1, which will be discussed in more detail below.

[0003] In particular, an electric motor should be understood as a machine used to convert electrical energy into kinetic energy and a machine used to convert kinetic energy into electrical energy. Specifically, it should be understood as both an electric motor and a generator.

[0004] In order to manufacture the mechanical components of such motors, such as stators or rotors, it is often necessary to shape conductive wires, connect them to each other, cut them, or otherwise process them. These wires can, in particular, have rectangular cross-sections, and can be designed as flat wires, square wires, or irregularly shaped wires.

[0005] In manufacturing electric motors for motor vehicles, production methods are often used to achieve, particularly economically, the production of high-performance components for the electric motor. This includes, in particular, the hairpin method. Here, the coil windings, especially the stator coil windings, are formed by a large number of wire segments, the ends of which are connected to each other. For example, EP 2684283B1, EP 1554794B1, and EP 1041696B1 describe apparatus and methods for connecting the ends of the hairpins to form the stator windings of the motor, wherein the ends of the wires are welded to each other. Each wire segment has a first leg, a second leg, and a bent section between the legs. The wire segment, hereinafter also referred to as a pin, can be, for example, U-shaped with a top bend as the bent section; a straight shape, i.e., a so-called I-shaped pin, is also feasible.

[0006] The manufacturing process of each wire, especially the hairpins or I-pins, precedes the manufacturing process of the motor. Next, the individual conductive wires or segments are bundled together as tightly as possible and soldered into a continuous conductive winding.

[0007] During the manufacturing process of each wire, the wire is pre-bent into a desired shape. This is typically achieved through several bends, for example, to produce other desired shapes for the top bend or bent sections. The bent sections often also include abrupt bends, the shape, function, and implementation of which are described and illustrated in more detail in DE 10 2018 106 978 A1. Furthermore, a top shape or bend—particularly an elbow—is formed between the legs of the I-pin. Examples of apparatus and methods for bending top shapes are described and illustrated in DE 10 2018106 980 A1.

[0008] Because the components of an electric motor are typically configured in a ring around the motor's axis of rotation, and the coil windings need to be configured accordingly in a crown-like or ring-like shape, the coils must be shaped in a manner that matches the curvature of the corresponding components. This is achieved using so-called free bending or 3D bending, which allows the use of equipment and methods known from the aforementioned documents US2014 / 0223727A1 and DE 10 2018 108656 A1.

[0009] Therefore, a die is used according to the equipment and method described in US2014 / 0223727 A1. When bending by the die, the wire is shaped via a contour tool. As seen from the previous considerations, the contour matches the corresponding component. Stator segments of different sizes with different coil windings require different shaped bending sections between the legs, thus requiring different contours for these bending sections. When bending by means of a die, a corresponding contour tool must be manufactured and used for each different contour to be shaped.

[0010] In contrast, DE 10 2018 108 656 A1 discloses an improved apparatus and an improved method in which 3D bending is performed via a fixed and pivotable fixture. Summary of the Invention

[0011] The present invention aims to further improve 3D bending equipment and 3D bending methods in terms of easier matching of different machine components and lower production costs.

[0012] To achieve this objective, the present invention provides a 3D bending apparatus and a 3D bending method. Advantageous designs are the subject of this discussion.

[0013] According to its first aspect, the present invention provides a 3D bending apparatus for bending a wire into a three-dimensional shape to manufacture machine components for an electric motor, the wire comprising a first leg, a second leg, and a bent section between the legs, the 3D bending apparatus comprising:

[0014] A first retaining element and a second retaining element, the first retaining element being used to retain the line on a first leg, and the second retaining element being used to retain the line on a second leg.

[0015] A first relative motion device is used to move a first holding element and a second holding element relative to each other in a first relative motion having a first axis of motion, so as to generate a torsion angle of an imaginary connecting line between the first leg and the central axis of the leg.

[0016] A second relative motion device is used to move the first holding element and the second holding element relative to each other in a second relative motion having a second axis of motion, so as to generate a torsion angle of the imaginary connecting line between the second leg and the central axis of the leg.

[0017] A third relative motion device is used to move the first holding element relative to the second holding element in a third relative motion having a third motion axis, so as to change the distance between the central axes of the legs.

[0018] Preferably, the first relative motion device is a first rotation or pivoting device, which is used to rotate or pivot the first holding element about a first rotation or pivoting axis that serves as the first motion axis.

[0019] Preferably, the third relative motion device is a linear motion device for causing the first holding element and the second holding element to move relative to each other along the direction of the first linear motion axis, which is the third motion axis.

[0020] Preferably, the second holding element is fixed, while the first holding element is configured to move by means of the first to third relative motion devices.

[0021] Preferably, the second motion device is a linear motion device for moving the first holding element along the direction of the second linear motion axis, which is the second motion axis.

[0022] Preferably, the second relative motion device is a second rotation or pivoting device, which is used to rotate or pivot the second holding element about a second rotation or pivoting axis that serves as the second motion axis.

[0023] Preferably, when the associated retaining element is used conventionally, one or more rotational or pivoting axes extend parallel to the central axis of the first and / or second leg with at least one directional component. Particularly preferably, when the associated retaining element is used conventionally, the corresponding rotational or pivoting axis coincides with the central axis of the first or second leg.

[0024] Preferably, when the associated retaining element is used conventionally, one or more linear motion axes extend transversely to the central axis of the first and / or second leg with at least one directional component. Particularly preferably, when the associated retaining element is used conventionally, the corresponding linear motion axis is perpendicular to the central axis of the associated leg.

[0025] Preferably, the first linear motion axis extends perpendicular to the second linear motion axis in at least one directional component. In particular, the first and second linear motion axes unfold into a motion plane in which the holding element can move freely relative to each other.

[0026] Preferably, the first rotational or pivotal axis extends substantially parallel to the second rotational or pivotal axis.

[0027] According to another aspect, the present invention relates to a 3D bending method for bending a wire into a three-dimensional shape to manufacture a machine component for an electric motor, the wire comprising a first leg, a second leg, and a segment bent between the legs, the method comprising:

[0028] a) By means of a first relative motion of the first leg and the second leg having a first axis of motion, the first leg is twisted by a first angle of torsion relative to an imaginary connecting line between the central axes of the first leg and the second leg.

[0029] b) By means of a second relative motion of the first leg and the second leg having a second axis of motion, the second leg is twisted by a second angle of torsion relative to an imaginary connecting line between the central axes of the first leg and the second leg, and

[0030] c) The distance between the central axes of the first and second legs is changed by means of a third relative motion of the first and second legs with a third axis of motion.

[0031] Preferably, the 3D bending method includes:

[0032] The first leg is held by means of a first holding element, and the second leg is held by means of a second holding element, and steps a), b) and c) are performed by means of the relative movement of the first holding element and the second holding element.

[0033] Preferably, step a) includes the step:

[0034] a1) To rotate or pivot the first leg about the first axis of rotation or pivot, which is the first axis of motion.

[0035] Preferably, step b) includes the following steps:

[0036] b1) Fix the second leg while rotating or pivoting the first leg, and move the position of the first leg along the second linear axis that serves as the second axis of motion.

[0037] Preferably, step b) includes the following steps:

[0038] b2) To rotate or pivot the second leg about the second axis of rotation or pivot, which is the second axis of motion.

[0039] Preferably, step c) includes the following steps:

[0040] c1) Make the first leg and the second leg move relative to each other along the first straight axis, which is the third axis of motion.

[0041] Preferably, one or more rotational or pivotal axes extend parallel to the central axis of the first and / or second leg with at least one directional component. Particularly preferably, the respective rotational or pivotal axis lies on the central axis of the associated leg.

[0042] Preferably, one or more linear motion axes extend transversely to the central axis of the first and / or second leg in at least one direction. Particularly preferably, the corresponding linear motion axes extend perpendicularly to the central axes of the first and second legs.

[0043] Preferably, the first linear motion axis extends perpendicular to the second linear motion axis in at least one directional component. Particularly preferably, these linear motion axes unfold into a motion plane in which the relative motion of the drive components is achieved via curves that can be freely selected.

[0044] Preferably, the first rotational or pivotal axis extends substantially parallel to the second rotational or pivotal axis.

[0045] Preferably, steps a) to c) are performed simultaneously or at least partially overlapping.

[0046] Preferably, the 3D bending device according to one of the above design schemes further includes a control device configured to control the 3D bending device for performing the 3D bending method according to one of the above design schemes.

[0047] According to another aspect, the present invention implements a computer program or computer program product including control instructions, which, when loaded into a control device of a 3D bending device according to one of the above-described designs, cause the 3D bending device to perform a 3D bending method according to one of the above-described designs.

[0048] A preferred embodiment of the present invention relates to an apparatus and method for bending coil sections.

[0049] Compared to existing techniques that rely on bending via a die, no separate contour tool is required for different shapes. Furthermore, the effects of backbends can be compensated for through simple testing and readjustment without the need for costly rework of the contour tool.

[0050] Compared to existing technologies with known pivotable clamps, adjustments can be made without altering the upstream processes that shape the bent sections—top bends, elbows, and / or abrupt bends. In particular, in embodiments of the invention, variations in distance or offset between the legs caused by 3D bending can be compensated for or corrected. Further advantages of the preferred design of the invention arise from the following detailed description of the preferred design. Attached Figure Description

[0051] Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Wherein are shown:

[0052] Figure 1 A side view showing a first embodiment of a line to be bent in the form of a hairpin or U-shaped pin;

[0053] Figure 2 A side view of a second embodiment of a line in the form of an I-shaped pin to be bent is shown;

[0054] Figure 3 Shown in Figure 1 or Figure 2 A top-down view of the line to be bent, taken from above, before the 3D bending.

[0055] Figure 4 Shown in Figure 1 or Figure 2 A top view of the line as seen from above after it has been curved in 3D;

[0056] Figure 5 This is a top view along the axial direction of a first embodiment of a stator lamination assembly, which is an example of a machine component of an electric motor. Figure 1 and Figure 4 The wires need to be inserted into the stator lamination group in a ring configuration;

[0057] Figure 6 A top view along the axial direction of a second embodiment of a stator lamination assembly, showing another example of a machine component of an electric motor. Figure 1 and Figure 4 The wires need to be inserted into the stator lamination group in a ring configuration;

[0058] Figure 7 Showing with Figure 4 A similar top view of the bent line after 3D bending is used to illustrate the desired parameters to be achieved through bending.

[0059] Figure 8 Showing the use of in accordance with Figures 1 to 4 and Figure 7A perspective view of a first embodiment of a 3D bending device for performing 3D bending online, wherein the first embodiment has a fixed clamp and a movable clamp;

[0060] Figure 9 Showing has Figure 4 and Figure 7 A graph of lines and motion curves, the motion curves being used to describe... Figure 8 The motion setting and programming of the movable fixtures of the 3D bending device.

[0061] Figure 10 Showing according to Figures 1 to 4 and Figure 7 A perspective view of a second embodiment of a 3D bending apparatus for performing 3D bending online, wherein the second embodiment has a first movable clamp and a second movable clamp; and

[0062] Figure 11 A view is shown of a fixed and movable clamp in a 3D bending device according to the prior art of DE 10 2018 108 656 A1, in order to illustrate the differences between embodiments of the present invention and the prior art, as well as their function and advantages. Detailed Implementation

[0063] exist Figure 1 and Figure 2 The diagram shows two different embodiments of line 10, which should be deformed into a coil section of a machine element of an electric motor. In the illustrated design, line 10 has a first leg 12, a second leg 14, and a bent section 16.

[0064] exist Figure 1 In the design, the line is bent into a hairpin or U-shape, wherein the bent segment 16 is configured as a top bend 18 having a first top leg 20 and a second top leg 22. The first top leg 20 and the second top leg 22 bend over each other. In other embodiments not shown in detail here, there may be different numbers of top legs 20, 22 and different numbers of bends in or on the bent segment 16. Due to the roof shape of the bent segment 16, the first leg 12 and the second leg 14 extend substantially parallel to each other with a gap s0 between them, wherein their direction of travel is 180° opposite when viewed along the line 10.

[0065] exist Figure 2 In the design scheme, the bent section 16 is configured as a bend 24. Legs 12 and 14 are staggered by a distance s0, but travel in the same direction along line 10. Due to the hairpin shape, according to... Figure 1 The design scheme of line 10 is also called hairpin 32 or U-pin. Due to the straight extension of legs 12 and 14 relative to each other, according to Figure 2The design scheme is also known as I-shaped pin 34.

[0066] Figure 5 and Figure 6 Two embodiments of a stator lamination assembly 26 are shown, which is used to form a stator 28, an example of a machine element of an electric motor. The stator lamination assembly 26 has slots 30 arranged circumferentially on its inner side, into which the legs 12, 14 of the wires 10 are inserted as coil sections to form coil windings after corresponding deformation and connection. Here, the top bends 18 of each wire 10 protrude at the ends of the stator lamination assembly 26, and the free ends of the legs 12, 14 are deformed by overlapping along the circumferential direction and then connected to the legs of other wires 10 to form coil windings. To achieve the highest possible packing density and suitability for use, the bent sections 16 should be pre-formed accordingly before inserting the wires 10 into the stator lamination assembly 26. The bent sections 16, and especially the top bends 18, then form the winding heads of the coil sections. In this case, Figure 2 The I-shaped pin can Figure 1 The hairpin 32 is used in some parts to form, for example, an interface or a special pin. Therefore, the I-pin should also be pre-formed in the bent section 16 accordingly.

[0067] exist Figure 5 and 6 In this configuration, the first leg 12 and the second leg 14 of the hairpin 32 are inserted into their respective slots. For example, each slot 30 accommodates a total of four coil segments, i.e., four wires 10 with corresponding legs 12, 14. Here, the first leg 12 and the second leg 14 are offset from each other not only in the circumferential direction but also in the radial position. Figure 5 and 6 In the example, the first leg 12 is inserted at the outermost radial position. Figure 5 and 6 In this example, the second leg 14 is inserted at the second outermost radial position. To achieve the corresponding abrupt change at the highest possible packaging density in the radial position, an abrupt bend 36 is provided in the bent section 16, as in... Figure 3 As shown in the diagram. Figure 3 Is Figure 1 Viewed from above Figure 1 The view of the corresponding line 10 in the diagram. For example, the top bend 18 between the two top legs 20, 22 has a shape that is presented in the diagram. Figure 3 The altered bend 36 shown is in the form of an altered bend head.

[0068] As in Figure 1As shown, the hairpin 32 has a so-called top bend 18. Accordingly, the line 10 is bent in the bend segment 16 such that the line has a first leg 12 and a second leg 14, the first and second legs extending substantially parallel to each other and connected to each other on one side via a roof-like portion of the line 10. Figure 1 The hairpin 32 shown has multiple angles 38, 40, 42, from which a top shape is generated, also referred to as a roof shape. Here, the angles 38, 40, 42 of the legs 12, 14 and the top legs 20, 22, and the length of the legs can be varied according to the desired shape. This variation can also be achieved within the wire 10 of the coil windings of the stator 28. Furthermore, it is necessary to manufacture or process wires 10 with different wire cross-sections as required.

[0069] exist Figure 1 The top bend shown is achieved through two-dimensional bending (hereinafter referred to as 2D bending), as described and illustrated in detail in DE10 2018 106 980A1. For further details regarding the bent top shape or top bend 18, please refer explicitly to that document. Figure 3 The implementation of the abrupt bend 36 shown is described and illustrated in detail in DE10 2018 106978A1, and therefore, for further details regarding the abrupt bend 36, please refer to that document.

[0070] For example, further Figure 5 and Figure 6 As shown, the stator lamination assembly 26 has an arcuate shape between the slots 30 into which the first leg 12 and the second leg 14 are inserted, and the bent segment 16 is correspondingly arcuately matched to the arcuate shape, so as to achieve a correspondingly high packing density of the top bend 18, thereby achieving a compact structure of the stator 28. Furthermore, as in Figure 5 and Figure 6 As shown, the slots 30 into which the first leg 12 and the second leg 14 are inserted are angled relative to each other in their orientation, such that the first leg 12 and the second leg 14 should have a corresponding angle relative to each other. This angle should also be achieved through the corresponding shaping of the top bend 18. For this purpose, the line 10 is shaped by 2D bending to... Figure 1 and Figure 2 One of the shapes shown and bent into Figure 3 After showing the shape with the abrupt bend 36, it is accordingly three-dimensionally bent to produce a free shape, as in Figure 4 As shown in the diagram. Figure 4 This shows the effect after performing free-form bending. Figure 1 The middle line 10 is observed from above. Figure 3 Similar view. Freeform bending is achieved through 3D bending 44.

[0071] In the following text, it should be based on Figures 5 to 10 An embodiment of a 3D bending apparatus for performing such 3D bending 44 and a 3D bending method for performing 3D bending 44 are described.

[0072] Figure 7 Here, viewed from above, the top bend 18 (similar to...) Figure 4 The image shows a line 10 in the form of a hairpin 32 that has been bent by 3D bending. Figure 8 A first embodiment of the 3D bending device 46 is shown. Figure 9 A diagram illustrating the setup of a first embodiment of the 3D bending device 46 is shown. Figure 10 A second embodiment of the 3D bending device 46 is shown.

[0073] Figure 5 and Figure 6 Two different embodiments of the stator 28 are shown, wherein the stator laminations 26 have different diameters D1, D2 and different numbers N of slots 30. For example, Figure 5 The stator lamination group 26 has a diameter D1 of 170 mm and a slot 30 with N=36, while Figure 6 The stator lamination group 26 has a diameter D2 of 220 mm and N = 48 slots 30. Of course, this is merely an example; completely different dimensions and a completely different number N of slots 30 can be set. However, as in... Figure 5 and Figure 6 As illustrated by examples of legs 12 and 14 used in different stators 28, there are different positions of legs 12 and 14 of hairpin 32 in the two stators and different torsion angles between legs 12 and 14. The distance s between legs 12 and 14 can also be different.

[0074] 3D bending 44 must be performed to achieve the desired parameters α1, α2, s for matchingly inserting legs 12, 14 into the slots 30 of the corresponding stators 28.

[0075] Therefore, as in Figure 7 As shown, a first twist angle α1 of the first leg 12 relative to the imaginary connecting line 48 between the central axes of the legs 12 and 14 must be set by 3D bending. Furthermore, a second twist angle α2 of the second leg 14 relative to the imaginary connecting line 48 must be set. After 3D bending, the distance between the central axes of the legs 12 and 14—along the imaginary connecting line 48—should correspond to a predetermined distance s. Before the 3D bending 44, line 10 has undergone two bending processes: the aforementioned top bending and abrupt bending.

[0076] With the help of the 3D bending device 46, the following parameters can be changed as independently as possible:

[0077] -The leg angle or torsion angle α1 of the first leg,

[0078] -The leg angle or torsion angle α2 of the second leg

[0079] - The distance s of the bent leg or the difference s-s0 before and after bending.

[0080] - The shape of the top or the shape of the top bend 18.

[0081] Features of the top shape, for example, can include curved shapes (see...) Figure 4 ) and / or the height of the top bend 18 and / or the size of the angles 38, 40, 42 of the top bend 18.

[0082] exist Figure 8 In the embodiment of the 3D bending device 46 shown, one of the legs 12, 14, such as the second leg 14, is fixed. Such an embodiment is particularly advantageous in manufacturing facilities for stators 28, where one of the legs 12, 14 is held by a conveyor system for mass production (serialization) of the stators 28. In this regard, a fixed delivery point and / or fixed position of the leg 14 to be fixed is advantageous. For example, a serialization facility is proposed in which one of the legs 14 is held by a conveyor system (not shown) and thus cannot move. Therefore, in the 3D bending device 46… Figure 8 The design scheme proposes that 3D bending can be achieved solely through the free movement of the other leg 12. Figure 10 An embodiment of the 3D bending device 46 is shown, wherein both the first leg 12 and the second leg 14 move during the 3D bending 44.

[0083] The two designs of the 3D bending device 46 are used to bend the line 10 into a three-dimensional shape and include a first holding element 50, a second holding element 52 and at least one first to third relative motion device 54, 56, 58.

[0084] The retaining elements 50 and 52 preferably have clamps 60 and 62, respectively. The first retaining element 50 can grasp the first leg 12 by means of the first clamp 60, thereby constituting a function for retaining the line 10 on the first leg 12. The second retaining element 52 can grasp the second leg 14 by means of the second clamp 62, thereby constituting a function for retaining the line 10 on the second leg 14.

[0085] The first retaining element 50 and the second retaining element 52 can move in a first relative motion having a first motion axis 64 by means of a first relative motion device 54, so as to twist the first leg 12 relative to the imaginary connecting line 48, thereby setting a first torsion angle α1 as the torsion angle of the first leg 12.

[0086] Accordingly, the second relative motion device 56 allows the first holding element 50 and the second holding element 52 to have relative motion along the second axis of motion 66, such that the second leg 14 is twisted relative to the imaginary connecting line 48, so as to set a second twist angle α2 as the twist angle of the second leg 14.

[0087] However, the 3D bending device 46 also has a third relative motion device 58, by means of which the first holding element 50 and the second holding element 52 can move relative to each other via a third motion axis 68, such that in the final state of the 3D bending 44, the distance s to be achieved between the central axes of the legs 12, 14 can be set independently of the torsion angles α1, α2. Figure 11 Unlike known devices that pivot about two vertical axes in space, the device shown in the diagram differs in that it is based on... Figure 8 and 10 In the 3D bending device 46, the legs 12 and 14 of the line 10 rotate in a defined manner, resulting in defined torsion angles α1 and α2 between the line 10, especially the legs of the hairpin 32, and the secant line—the imaginary connecting line 48. Simultaneously, the distance s between the leg axes can be defined. Additionally, the forming of the top curved portion 18 or the bent segment 16 can be determined by changing the distance achieved through bending.

[0088] In order to determine the distance s of legs 12 and 14 at the end of 3D bending 44 independently of leg angles α1 and α2, it is proposed in 3D bending device 46 that legs 12 and 14 can move relative to each other with three degrees of freedom—first to third axes of motion 64, 66, and 68.

[0089] The first relative motion device 54 and the second relative motion device 56 are configured such that the torsion occurs around the legs 12 and 14, respectively, preferably around the central axis of the line. Therefore, the rotational movement of the legs 12 and 14 does not cause a change in the distance s between the legs 12 and 14.

[0090] Two design schemes for the 3D bending device 46 Figure 8 and 10 As shown in [the image]. According to [the source]... Figure 10 In the design scheme, the two legs 12 and 14 twist around the axis and are positioned separately along the third axis. Based on... Figure 8 In this design, one leg 14 remains fixed, while the other leg 12 is positioned between two axes and twists about a third axis. This design is particularly suitable for series facilities where hairpins or other lines 10 are transported by means of a conveyor system.

[0091] exist Figure 8The 3D bending device 46 shown is configured as a bending unit 70 with fixed legs 14 for performing 3D bending 44. The 3D bending device 46 has a machine tool or frame 72, on which a second holding element 52 is fixed and thus immovable. A second clamp 62 is located on the second holding element 52, and in this position, the second clamp is immovable and thus a fixed clamp.

[0092] The first clamp 60 and the second clamp 62 each have clamping jaws 74 and 76 that can move toward and away from each other, and one or more actuators 78 for moving the clamping jaws 74 and 76 toward and away from each other.

[0093] Therefore, the second clamp 62 is configured as Figure 8 In the case of a fixed clamp, clamping claws 74 and 76 are brought into a holding portion, in which the second leg 14 is held in a fixed preset position throughout the 3D bending process.

[0094] The bending unit 70 with fixed leg 14 also has a cross slider 80, which has a first linear motion device 82 for moving the first holding element 50 along the direction of the first linear motion axis x and a second linear motion device 84 for moving the first holding element 50 along the direction of the second linear motion axis y.

[0095] The first linear motion device 82 has a first guide device 86 oriented in the x-direction for guiding the first sliding element 88 and a first linear motion actuator 90 for driving the motion of the first sliding element 88 along the x-direction of the first linear motion axis.

[0096] The second linear motion device 84 has a second guide device 92 oriented in the y-direction at the first sliding element 88, the second guide device being used to guide the second sliding element 94, and the second linear motion device has a second linear motion actuator 96, the second linear motion actuator being used to drive the movement of the second sliding element in the direction of the second linear motion axis y.

[0097] A first rotation or pivoting device 98 is provided on the second sliding element 94 for rotating or pivoting the first holding element 50 about a first rotation or pivoting axis 100. The first rotation or pivoting device 98 has a first rotation actuator 102 for driving the rotational movement of the first holding element 50.

[0098] The first holding element 50 has a corresponding rotatable base element 104 on which an actuator 78 and clamping jaws 74, 76 of the first clamp 60 are disposed. Accordingly, the base element 104 has a movement guide for the clamping jaws 74, 76. Between the clamping jaws 74, 76 of the second clamp 62, the first leg 12 of the line can be held in a holding position. The first clamp 62 is configured such that the first leg 12 is held such that its central axis lies on the first rotation or pivot axis 100.

[0099] The 3D bending device 46 also includes a control device 106, by means of which the actuators can be controlled according to computer software stored or loaded in the actuators 78, 90, 96, 102. The control is performed such that a first torsion angle α1 of the first leg is set by means of a first rotation or pivoting device 98, while the first holding element 50, via a cross slider 80, sets a second torsion angle α2 of the second leg 14 and a distance s between legs 12, 14 by means of movement along a first linear motion axis x and along a second linear motion axis y corresponding to a pre-calculated, thus preset motion curve K2.

[0100] Therefore, the first relative motion device 54 is formed by the first rotation or pivoting device 98. The second relative motion device 56 largely utilizes motion along the second linear motion axis y, and is thus mainly formed by the second linear motion device 84. The third relative motion device 58 is realized by providing motion along the first linear motion axis x through the provision of the third motion axis 78. Therefore, the third relative motion device 58 is essentially formed by the first linear motion device 82.

[0101] After the cross slider 80 can traverse every point in the xy-plane in two dimensions, and thus also traverse any curve within the xy-plane, the actual orientation of the first linear motion axis x and the second linear motion axis y is arbitrary, as long as a plane is unfolded from it; that is, it does not extend parallel or coincidentally. To realize the relative motion devices 54, 56, 58, according to this design of the 3D bending device 46, it is only important that three degrees of freedom are correspondingly provided for movement in the xy-plane and rotation or pivoting about a z-axis—the first rotation axis 100—preferably perpendicular to the xy-plane. In a variant, for example, the cross slider 80 operating in the xy-plane according to Cartesian coordinates can be replaced by any other mechanism for traversing freely configurable curves in the xy-plane, such as a linear motion mechanism that rotates on a frame about a main rotation axis to operate according to cylindrical coordinates.

[0102] The first clamp 60 is configured such that the line 100 is held such that the central axis of the movable first leg 12 is located within the rotation axis 100 of the clamp 60. Alternatively, the method of bending can be adjusted to compensate for the offset of the central axis of the line 10 relative to the torsional axis 100.

[0103] The following is based on Figure 9 The view in the diagram is described according to Figure 8 A 3D bending method for performing 3D bending is to be executed on a bending unit 70 with fixed legs 14.

[0104] Figure 9 A top view in the xy plane is shown, where the units in the x and y directions are millimeters. Here, the central axis of the second leg 14, which acts as a fixed leg, is chosen as the zero point. The central axis is fixed in position by means of the second clamp 62 holding the second leg 14 in place.

[0105] In the initial state, the first leg 12 is located at position P0, which is determined by the initial distance s0 between legs 12 and 14 after the top bend and abrupt bend. Curve K0 shows the radius having the distance s0 between legs 12 and 14 in the initial state. Here, reference is made to the center of clamps 60 and 62. For example, in the initial state, the distance s0 between legs 12 and 14 is 86 mm, and correspondingly, a circle with a radius of 86 mm can be considered as curve K0. Furthermore, as an example assumption, 80 mm is preset as the desired distance s between legs 12 and 14 in the final state. The radius of curve K1 has this distance s between legs 12 and 14 in the final state.

[0106] The transition curve between these two radii K0 and K1 is now selected as the motion curve K2 of the first clamp 60 relative to the second clamp 62, starting at position P0 in the initial state and ending at the desired termination position P1 of the first leg 12 relative to the second leg 14. This forms a freeform curve K2, which is programmed as the motion curve for the movement of the first clamp 60 in the xy plane. This motion curve K0 is correspondingly tracked by linear motion devices 82 and 84. Simultaneously, the torsion angle α1 of the first leg 12 is set by rotating the first clamp 60 about the first rotation axis 100. The torsion angle α2 of the second leg 14 is derived from the freeform curve K2.

[0107] The control device 106 can be easily programmed using the preset.

[0108] exist Figure 10The diagram shows a second embodiment of the 3D bending device 46, configured as a bending unit 108 for 3D bending with two movable legs 12, 14. This design of the 3D bending device 46 also includes a machine tool or frame 72 on which a linear motion device 82 is mounted for relative movement of the first holding element 50 and the second holding element 52 along a first linear motion axis x. For this purpose, a first guide device 86 is configured on the frame 72, on which a first sliding element 88 can move along the first linear motion axis x. Furthermore, the linear motion device 82 has a second guide device 92 for relative movement of the holding elements 50, 52 along the linear motion axis x. This second guide device is also fixed to the frame 72 and oriented along the x-direction, so that the second sliding element 94 can also move along the first linear motion axis x.

[0109] In one design, the first sliding element 88 and the second sliding element 94 can be moved via a transmission device (not shown) using a common first linear motion actuator 90, which converts the driving motion of the first linear motion actuator 90 into the reverse motion of the sliding elements 88 and 94. In another embodiment, the first sliding element 88 can be moved by means of the first linear motion actuator 90, while the second sliding element 94 can be moved by means of the second linear motion actuator 96. The reverse motion of the first holding element 50 and the second holding element 52 can be correspondingly controlled by the controller 106 to manipulate the linear motion actuators 90 and 96.

[0110] A first rotation or pivoting device 98 is provided on the first sliding element 88, which enables the first holding element 50 to rotate about the first rotation or pivot axis 100 by means of a first rotation actuator 102. A second rotation or pivoting device 110 is provided on the second sliding element 94, which enables the second holding element 52 to rotate or pivot about the second rotation or pivot axis 112. To drive this movement, the second rotation or pivoting device 110 has a second rotation actuator 114.

[0111] In this design, components 50 and 52 are designed identically or in mirror image. The base component 104 has guides and actuators 78 for the corresponding clamping jaws 74 and 76. The first and second clamps 60 and 62 are configured such that the corresponding legs 12 and 14 can be held such that their respective central axes coincide with the corresponding rotational or pivoting axes 100 and 112. Alternatively, compensation can be made via corresponding motion modes when the rotational axes 100 and 112 do not coincide with the central axes.

[0112] The control device 106 is configured to manipulate the actuators 78, 90, 96, 102, and 114, and is programmed to perform 3D bending 44 with at least three degrees of freedom.

[0113] The first rotating or pivoting device 98 forms a first relative motion device 54 having a first rotating or pivoting axis 100 as a first motion axis 64. The second rotating or pivoting device 110 forms a second relative motion device 56 having a second rotating or pivoting axis 112 as a second motion axis 66. The linear motion device 82 for causing the holding elements 50 and 52 to move relative to each other along the direction of the first linear motion axis x forms a third relative motion device 58 having the first linear motion axis x as a third motion axis 68.

[0114] Therefore, the bending unit 108, which has two movable legs 12, 14 for bending, has: a first linear axis and a parallel second linear axis, so that the first clamp 60 and the second clamp 62 move toward each other and away from each other in opposite directions; a first torsion axis—a first rotation or pivot axis 100—for setting a first torsion angle α1; and a second torsion axis—a second rotation or pivot axis 112—for setting a second torsion angle α2.

[0115] By means of the 3D bending 44 of the bending unit 108 which bends by means of the two movable legs 12, 14, the two rotating or pivoting devices 98, 110 pivot about the corresponding central axis of the legs 12, 14—the axis of rotation. At the same time, the sliding elements 88, 94 move relative to each other.

[0116] Instead of sliding elements 88 and 94, the relative motion of holding elements 50 and 52 can also be achieved by any other feasible type of motion along a straight axis.

[0117] Thus, in the 3D motion device according to the design scheme of the present invention, at least three relative motion devices 54, 56, 58 are provided so as to perform relative motion of the holding elements 50, 52 for holding the legs 12, 14 by means of at least three motion axes 64, 66, 68.

[0118] and Figure 11 The prior art of 3D bending equipment used to date is shown, the 3D bending equipment having a fixed clamp 62 and a movable clamp 60 that can pivot about two axes of motion.

[0119] In the pivotable clamp 62, the elastic deformation of the line to be bent can be compensated for by over-bending. The angular positions of the first clamp 60 and the second clamp 62 relative to each other generate corresponding torsion angles α1 and α2 relative to the connecting lines of legs 12 and 14. According to... Figure 11 In the prior art, the distance between the bent legs is present. Different leg distances are obtained with the same initial geometry and varying torsion angles through a fixed axis. This means that if the parameters α1, α2, s of the free-form bending change, the upstream process of 2D bending must be altered. The cost of finding these parameters is relatively high. Furthermore, the free shape is generated by bending with a fixed axis, making the shape of the bent segment 16 fixed and less susceptible to influence. The angular positions of the two clamps 60, 62 relative to each other in known 3D bending devices always produce a preset distance between the bent legs 12, 14 under the same initial conditions. The three-dimensional shape in the upper region of the line is generated from the distance between the legs in the unbent and bent states, as well as the leg angles—torsion angles α1, α2—and the distance of the pivoted leg 12. If this three-dimensional shape must be changed, the additional movable forming element must bend the upper region while clamped.

[0120] However, according to Figure 8 and Figure 10 In the design of the 3D bending device 46, input parameters can be directly implemented, namely the first twist angle α1, the second twist angle α2, the initial distance s0 of legs 12 and 14, and the final distance s of legs 12 and 14. Furthermore, it is feasible to control the forming of free-form bending during the bending process.

[0121] By more specifically tuning the parameters, the 3D bending process can be considered more independently of the 2D bending process. This simplifies the startup process because fewer iterative steps must be performed when looking up the parameters. Figure 11 In the design scheme, the distance between legs 12 and 14 may not be reduced without changing the torsion angles α1 and α2 of legs 12 and 14.

[0122] The gained degrees of freedom allow for more uniform formation of the desired line shape. Based on... Figure 11 In the design scheme, the forced position (Zwangslage) and top shape of legs 12 and 14 are generated by the angular position. In many cases, additional bending of the top is required to obtain the desired pin / line shape.

[0123] The decoupling of leg torsion and the relative positions of the legs in the 3D bending device 46 according to the present invention also allows for more complex free-form bending. Therefore, for example, different phases of the motor output can be achieved at different angles.

[0124] Therefore, in order to simplify the start-up operation and parameter changes in online 3D bending, the present invention realizes a 3D bending device 46 and a 3D bending method for bending line 10, wherein line 10 is held on a first leg 12 and a second leg 14, and the legs 12, 14 move in a first to third relative motion with first to third motion axes 64, 66, 68 by means of first to third relative motion devices 54, 56, 58, so as to change the torsion angles α1, α2 of the first leg and the second leg 12, 14 and the distances s0, s between the central axes of the legs 12, 14 in a manner that can be set independently of each other. In other words, in this 3D bending device and in the 3D bending method, the legs 12, 14 of the line (10) can move relative to each other with at least three degrees of freedom.

[0125] List of reference numerals

[0126] 10 lines

[0127] 12 First Leg

[0128] 14 Second Leg

[0129] 16. Bending sections

[0130] 18. Top Curve

[0131] 20 First top leg

[0132] 22 Second top leg

[0133] 24 elbows

[0134] 26 stator laminations

[0135] 28 stators

[0136] 30 slots

[0137] 32 hairpins

[0138] 34 I-shaped pin

[0139] 36 Abrupt bend

[0140] 38 First angle (the bent section)

[0141] 40. Second angle (the bent section)

[0142] 42. Third angle (the bent section)

[0143] 44 3D bending

[0144] 46 3D Bending Equipment

[0145] 48. Imaginary connecting lines

[0146] 50 First holding element

[0147] 52 Second holding element

[0148] 54 First relative motion device

[0149] 56 Second relative motion device

[0150] 58 Third relative motion device

[0151] 60 First clamp

[0152] 62 Second clamp

[0153] 64 First axis of motion

[0154] 66 Second axis of motion

[0155] 68 Third axis of motion

[0156] 70. Bending unit (fixed leg)

[0157] 72 racks

[0158] 74 First clamping claw

[0159] 76 Second clamping claw

[0160] 78. Actuator (clamp)

[0161] 80 Cross Slider

[0162] 82 First linear motion device (first linear motion axis x)

[0163] 84 Second linear motion device (second linear motion axis y)

[0164] 86 First guiding device

[0165] 88 First sliding element

[0166] 90 First linear motion actuator

[0167] 92 Second guiding device

[0168] 94 Second sliding element

[0169] 96 Second linear motion actuator

[0170] 98 First rotating or pivoting device

[0171] 100 First rotational or pivotal axis

[0172] 102 First Rotary Actuator

[0173] 104 Basic Components

[0174] 106 Control Device

[0175] 108 Bending Units (Two Movable Legs)

[0176] 110 Second rotating or pivoting device

[0177] 112 Second rotational or pivotal axis

[0178] 114 Second Rotary Actuator

[0179] α1 Twist angle of the first leg

[0180] α2 Twist angle of the second leg

[0181] Position of P0 at the initial state

[0182] K0 has the radius of the distance between the legs in the initial state.

[0183] K1 has the radius of the leg distance in the final state.

[0184] K2 Freeform Curve

[0185] s0 is the distance between the legs (initial state).

[0186] s represents the distance between legs (final state).

[0187] x First linear motion axis

[0188] y Second linear motion axis

Claims

1. A 3D bending device (46) for bending a wire (10) into a three-dimensional shape to manufacture a machine element of an electric motor, the wire comprising a first leg (12), a second leg (14), and a bent segment (16) between the first and second legs (12, 14), the 3D bending device comprising: A first retaining element (50) and a second retaining element (52), the first retaining element being used to retain the line (10) on the first leg (12) and the second retaining element being used to retain the line (10) on the second leg (14). A first relative motion device (54) is used to move the first retaining element (50) and the second retaining element (52) relative to each other in a first relative motion having a first motion axis (64) to generate a twist angle (α1) of the first leg (12) relative to an imaginary connecting line (48) between the central axes of the first and second legs (12, 14), wherein the imaginary connecting line (48) is a straight line extending at the free ends of the first and second legs (12, 14) between the central axes of the first and second legs (12, 14). A second relative motion device (56) is used to move the first retaining element (50) and the second retaining element (52) relative to each other in a second relative motion having a second motion axis (66), so as to generate a torsion angle (α2) of the second leg (14) relative to an imaginary connecting line (48) between the central axes of the first and second legs (12, 14), and A third relative motion device (58) is used to move the first holding element (50) relative to the second holding element (52) in a third relative motion having a third motion axis (68) in order to change the distance (s0, s) between the central axes of the first and second legs (12, 14), wherein the third relative motion device (58) is a first linear motion device (82) for moving the first holding element (50) and the second holding element (52) relative to each other along a first linear motion axis (x) which is the third motion axis (68).

2. The 3D bending device (46) according to claim 1. Its features are, The first relative motion device (54) is a first rotation or pivoting device (98) for rotating or pivoting the first holding element (50) about a first rotation or pivoting axis (100) which is a first motion axis (64).

3. The 3D bending device (46) according to claim 1. Its features are, The second retaining element (52) is configured to be fixed, while the first retaining element (50) is configured to be movable by means of the first to third relative motion devices (54, 56, 58), and / or The second relative motion device (56) is a second linear motion device (84) for moving the first holding element (50) along the second linear motion axis (y), which is the second motion axis (66).

4. The 3D bending device (46) according to claim 2. Its features are, The second relative motion device (56) is a second rotation or pivoting device (110) for rotating or pivoting the second holding element (50) about a second rotation or pivoting axis (112) which is the second motion axis (66).

5. The 3D bending device (46) according to claim 4. Its features are, When the associated first and second retaining elements (50, 52) are used conventionally, the corresponding first and second rotational or pivoting axes (100, 112) extend with at least one directional component parallel to the central axis of the first leg and / or the second leg (12, 14), and / or When the associated first and second retaining elements are used conventionally, the corresponding first and second linear motion axes (x, y) extend laterally to the central axis of the first leg and / or the second leg (12, 14) with at least one directional component, and / or The first linear motion axis (x) extends with at least one directional component perpendicular to the second linear motion axis (y), and / or The first rotation or pivot axis (100) extends substantially parallel to the second rotation or pivot axis (112).

6. A 3D bending method for bending a wire (10) into a three-dimensional shape to manufacture a machine element of an electric motor, the wire having a first leg (12), a second leg (14), and a bent segment (16) between the first and second legs (12, 14), the 3D bending method comprising: a) By means of the first relative motion of the first leg (12) and the second leg (14) having a first axis of motion (64), the first leg (12) is twisted by a first twist angle (α1) relative to an imaginary connecting line (48) between the central axes of the first leg and the second leg (12, 14). b) By means of the second relative motion of the first leg (12) and the second leg (14) having a second axis of motion (66), the second leg (14) is twisted by a second twist angle (α2) relative to an imaginary connecting line (48) between the central axes of the first leg and the second leg (12, 14), and c) By means of the third relative motion of the first leg and the second leg (12, 14) having a third axis of motion (68), the distance (s0, s) between the central axes of the first leg and the second leg (12, 14) is changed. Step c) includes: c1) causes the first leg and the second leg (12, 14) to move relative to each other along the first linear motion axis (x), which is the third motion axis (68).

7. The 3D bending method according to claim 6, comprising: The first leg (12) is held by means of the first holding element (50), and the second leg (14) is held by means of the second holding element (52), and steps a), b) and c) are performed by means of the relative movement of the first holding element and the second holding element (50, 52).

8. The 3D bending method according to any one of claims 6 to 7, Its features are, Step a) includes: a1) To rotate or pivot the first leg (12) about the first rotation or pivot axis (100) which is the first axis of motion (64).

9. The 3D bending method according to any one of claims 6 to 7, Its features are, Step b) includes: b1) Fix the second leg (14) while rotating or pivoting the first leg (12), and move the position of the first leg (12) along the second linear motion axis (y) which is the second motion axis (66), or b2) To rotate or pivot the second leg (12) about the second rotation or pivot axis (112) which is the second axis of motion (66).

10. The 3D bending method according to any one of claims 6 to 7, Its features are, The corresponding rotation or pivot axis (100, 112) extends with at least one directional component parallel to the central axis of the first leg and / or the second leg (12, 14), and / or The corresponding linear motion axes (x, y) extend laterally to the central axis of the first leg and / or the second leg (12, 14) with at least one directional component, and / or The first linear motion axis (x) extends with at least one directional component perpendicular to the second linear motion axis (y), and / or The first rotational or pivotal axis (100) extends substantially parallel to the second rotational or pivotal axis (112).

11. The 3D bending method according to any one of claims 6 to 7, Its features are, Steps a) to c) are performed simultaneously or at least partially overlapping.

12. The 3D bending apparatus (46) according to any one of claims 1 to 5 further includes a control device (106) configured to control the 3D bending apparatus (46) to perform the 3D bending method according to any one of claims 6 to 11.

13. A computer program or computer program product comprising control instructions that, when loaded into a control device (106) of a 3D bending apparatus (46) according to claim 12, cause the 3D bending apparatus (46) to perform a 3D bending method according to any one of claims 6 to 11.

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