Method and device for manufacturing a wire outline for a coil element of a coil winding of an electric machine

Abstract

The invention relates to a method for producing a wire contour for a coil element of an electric machine winding, comprising: providing a bending unit (6) with forming elements (12) that can be moved along a process path (4); receiving and holding a wire section (9) in the bending unit (6) in a receiving area (8) along the process path (4); carrying out a bending process in which the wire section (9) is shaped into a wire contour for a coil element of an electric machine winding by the forming elements (12) of the bending unit (6); and releasing the wire contour from the bending unit (6) in a delivery area (14) that is arranged along the process path (4) at a distance from the receiving area (8).The bending process further comprises the following: moving the bending unit (6) with the forming elements (12) by a feeding motion between the receiving zone (8) and the output zone (14), and moving the forming elements (12) relative to each other by a bending motion to shape the wire segment (9) received in the bending unit (6) according to its contour. A device is also created for producing the wire contour for a coil element of an electric motor winding.

Description

[0001] The invention relates to a method and a device for producing a wire contour for a coil element of a coil winding of an electric machine. background

[0002] To manufacture coil elements for the winding of an electric machine, sections or pieces of electrically conductive wire are regularly shaped using a bending or forming device. Such coil elements are known, for example, as hairpins or wave windings.

[0003] Document DE 103 28 955 A1 discloses a method and a device for forming (bending) shaft windings for rotor and stator laminated cores of electrical machines. The shaft winding is produced in a forming process in which superimposed disks have circumferential forming projections on their outer surfaces. During the manufacturing process, the two superimposed disks rotate continuously together. With the aid of a wire guide device that rotates intermittently, the wire to be formed or bent is alternately laid around the forming projections on the two disks. In this way, the shaft winding is created.

[0004] Document DE 10 2017 127 634 A1 describes a device and a method for bending and manufacturing wave windings for coil windings of electrical machines. Bending units, each formed with bending or forming elements, are provided for bending the wire. The forming elements assigned to a bending unit are slidably mounted along a first and a second linear guide. After the wire to be bent is inserted, the forming elements are displaced relative to each other, which includes a displacement along the first and second linear guides as well as a pivoting movement. At the end of this displacement along the first and second linear guides, the forming elements are arranged side by side, and the wire is bent into a wave winding.Afterwards, the wave winding can be removed from the bending unit, and the forming elements are returned to their starting position in the stationary bending unit to perform a new bending or forming operation. This means that a new bending operation can only begin with the bending unit after the wire section previously formed into the wave winding has been removed from the bending unit, in order to then reload it with a straight wire section.

[0005] Document US 2011 / 0277315A1 relates to a method for manufacturing a stator coil and a machine for manufacturing a stator coil for an electrically rotating machine. The stator coil manufacturing machine has a rotatable holder that supports pairs of forming dies and is movable along a track to press sections of a conductor wire into in-slot sections that are arranged in slots of a stator core. The machine further has coil end sections that extend outside the slots.The process includes the forming of coil end sections, in which press elements of each of the forming press pairs are brought close together one after the other to form the coil end sections, and the forming of slot sections, in which the forming press pairs are moved forward on the loop track in contact with the cam mechanism and, in addition, selected of the forming press pairs are moved one after the other in a direction perpendicular to the track to form the slot sections.

[0006] Document DE 10 2016 203 167 A1 discloses a device for producing a wave-shaped bent wire segment for use as a stator winding in an electric machine, comprising a linear guide and several forming tools that are longitudinally displaceable and rotatable on the linear guide and each have a receiving area for fixing the wire segment to be bent. The forming tools can be rotated in opposite directions and simultaneously moved together along the linear guide to bend the wire segment fixed to them into a wave shape. Furthermore, a method for producing a wave-shaped bent wire segment, which can be carried out with this device, is described. Summary

[0007] The object of the invention is to provide a method and a device for producing a wire contour for a coil element of a coil winding of an electrical machine, with which the process control during bending or forming of the wire contour can be optimized.

[0008] To solve this problem, a method and a device for producing a wire contour for a coil element of a coil winding of an electrical machine are provided according to independent claims 1 and 14. Embodiments are the subject of dependent subclaims.

[0009] According to one aspect, a method for producing a wire contour for a coil element of a coil winding of an electrical machine is provided, comprising the following: providing a bending unit with forming elements that is movable along a process path; receiving and clamping a wire section in the bending unit in a receiving area along the process path; performing a bending operation in which the wire section is formed or bent by means of the forming elements of the bending unit into a wire contour for a coil element of a coil winding of an electrical machine; and releasing the wire contour from the bending unit in a delivery area that is arranged along the process path at a distance from the receiving area.The bending process further includes the following: moving the bending unit with the forming elements by means of a feed movement between the receiving area and the delivery area, and moving the forming elements relative to each other by means of a bending movement in order to shape the wire section received in the bending unit into the wire contour.

[0010] According to another aspect, a device for producing a wire contour for a coil element of a coil winding of an electrical machine is created, which has the following: a process section; a bending unit with forming elements and a control and operating device which is assigned to the process section and is set up to move the bending unit along the process section by means of a feed movement during bending operation.

[0011] The control and operating equipment is further configured to control the following: receiving and clamping a wire section in the bending unit at a receiving area along the process path; performing a bending operation in which the wire section is formed by the bending unit's forming elements into a wire contour for a coil element of a coil winding of an electrical machine; and releasing the wire contour from the bending unit at a discharge area located along the process path at a distance from the receiving area. The bending operation further comprises: moving the bending unit with the forming elements by means of a feed motion between the receiving area and the discharge area, and moving the forming elements relative to each other by means of a bending motion to form the wire section received in the bending unit into the wire contour.

[0012] During the forming process for creating the wire contour or shape for the coil element, which essentially comprises the bending process but may also include supplementary forming steps, various movements or displacements occur in connection with the operation of the bending unit within the process line. On the one hand, the bending unit, along with its associated bending or forming elements, is moved forward along the process line (feed movement). Additionally, the forming elements are displaced relative to each other (bending or forming movement) to shape the wire section into the wire contour, in particular to bend it. In this way, the wire section, which is picked up and clamped in the receiving area of ​​the process line, is moved to the discharge area, located at a distance from the receiving area, where the produced wire contour is removed from the bending unit.This process moves the bending unit, along with its associated forming elements, as a complete unit from the receiving area to the discharge area along the process path. Furthermore, during the bending process, the forming elements of the bending unit are moved relative to each other to shape the original wire section into the desired wire contour. After the bending unit has left the receiving area with the collected wire section, another bending unit can similarly pick up another wire section. This enables a continuous process if multiple bending units, each with its associated forming elements, are positioned along the process path and can be moved between them.

[0013] When forming the wire section into the wire contour, which is essentially or predominantly carried out by bending but may also include supplementary forming steps, the forming elements of the bending unit can perform a pivoting movement and / or a translational movement (linear movement), whereby the forming elements of the bending unit shift relative to each other. Bending units with associated forming elements are known as such in various embodiments.

[0014] The bending movement of the forming elements can, in one embodiment, be an externally imposed movement, for example, due to the displacement of the bending unit with the forming elements along a guide element of the process path. The bending unit is displaced along the guide element by means of the feed movement. One or more bending units can perform the feed movement along one of the guide elements assigned to the bending unit(s) along the process path. It is possible that the forming elements of the bending unit are assigned to different guide elements, the distance between which changes along the process path, thus necessarily leading to a relative displacement of the forming elements in order to shape the wire section into the wire contour.For example, guide elements can drift apart, forcing a pivoting or rotating movement for individual shaping elements in order to bend or shape the wire section in the bending unit.

[0015] The feed movement and the bending movement can be performed at least partially simultaneously. This means that the feed of the bending unit, with the wire section it holds, occurs at the same time as the bending or forming of the wire section to the desired wire contour. The feed movement and the bending movement overlap, at least in terms of timing.

[0016] The bending unit can be continuously moved along the process path by means of the feed movement during the relative displacement of the forming elements by means of the bending motion to shape the wire section. In this embodiment, the feed movement for relocating the bending unit with the wire section held therein is performed continuously and without interruption, while the wire section is formed into the wire contour by means of the bending motion.

[0017] During the relative displacement of the forming elements during the bending movement to shape the wire section, the bending unit can remain in a rest position, at least temporarily, along the process path, free from the feed movement. In this alternative embodiment, the feed movement is temporarily interrupted, for example, completely or partially during the bending movement to shape the wire section. The feed can be interrupted, for example, when the wire section is picked up in the bending unit. Alternatively or additionally, the feed can be temporarily suspended when the wire section is clamped in the bending unit. An interruption can also be provided, alternatively or additionally, when the wire contour is released from the bending unit.

[0018] The bending unit can be moved along the process path, at least temporarily, by means of the feed motion while the wire section is being picked up and / or clamped. The bending unit is also moved or repositioned along the process path, at least temporarily, by means of the feed motion while the wire section is being picked up and / or clamped within the bending unit. As a result of the feed motion during picking up the wire section, a defined wire tension can be applied to the wire section. It can be provided that the feed motion is performed continuously and without interruption during picking up and / or clamping the wire section. In this way, the time required to load the bending unit with the wire section to be formed can be minimized, and the loading process (picking up and clamping) can be carried out without stopping the bending unit.

[0019] The bending unit can be moved along the process path, at least temporarily, by means of the feed motion while the wire contour is being released from the bending unit. It can also be provided that the bending unit with the forming elements is moved continuously along the process path by means of the feed motion while the wire contour is being released from the bending unit. By performing the feed motion at least temporarily or even continuously while the wire contour is being released, the time required for releasing the wire contour from the bending unit can be minimized in the process control. It is also possible to release the wire contour from the bending unit without stopping during such unloading of the bending unit.

[0020] The wire section can be subjected to a predetermined tensile stress. This stress can be applied at least when the wire section is picked up by the bending unit. The predetermined tensile stress is applied before clamping and maintained until clamping. For this purpose, the feed movement of the bending unit along the process path can be controlled accordingly, so that a lower or higher tensile stress is exerted on the wire section.

[0021] The wire section can be pre-processed in the process line before being picked up by the bending unit. Pre-processing can include, for example, straightening the wire section. Alternatively or additionally, an electrical insulation test and / or a check of the wire geometry or contour can be performed as preparation. During pre-processing, the wire section can be moved temporarily or continuously along the process line. This can be achieved, for example, by moving one of the bending units, which is to pick up the current wire section, along the process chain by means of a feed mechanism, thus pulling the current wire section behind it. In this way, the time required for pre-processing the wire section along the process line can be minimized. In particular, pre-processing of the wire section without stopping can be implemented.

[0022] The wire section can be separated from a continuous wire supply before the bending process begins. The continuous wire supply can, for example, be unwound from a wire spool. While the wire section is being separated from the continuous wire supply, the feed movement of the bending unit can be continued, at least intermittently or continuously, so that the wire section is moved along the process path during the separation process, thus minimizing the time required for this step. The separation of the wire section from the continuous wire supply can be performed at various alternative times, for example, before the wire section is picked up by the bending unit, or alternatively, after picking up and before clamping the wire section in the bending unit. In an alternative embodiment, the bending process can be provided that the bending process has already begun when the wire section is separated from the continuous wire supply.

[0023] The wire section for the bending unit can be fed from a wire reservoir. After the wire section is clamped in the bending unit, the feed movement of the bending unit along the process path draws in a subsequent wire section from the wire reservoir and feeds it to a subsequent bending unit. A subsequent wire section is thus forcibly drawn or inserted into the process path to be received and clamped in the following bending unit, whereupon the subsequent wire section can also be formed into the wire contour. The subsequent or further bending units can be designed and operated in a manner consistent with the bending unit. The feed movement of the bending unit with the clamped wire section within it, in turn, feeds further wire sections into the process path.

[0024] After the wire contour is released from the bending unit, the wire is fed along the process path by means of a feed motion to a further or subsequent bending operation, in which another wire section is bent into a further wire contour using the forming elements of the bending unit. This further wire contour can be identical to the previous wire contour or different from it, for example, in terms of shape. It is possible to configure different bending units with their respective forming elements to produce wire contours with different shapes in successive bending operations. However, it is also possible to produce wire contours with the same shape successively using the bending units.

[0025] The bending unit can be continuously moved along the process path by means of the feed motion. The feed motion is performed continuously, so that the bending unit (and optionally other bending units) is moved along the process path essentially without rest positions, with the various process steps being carried out during the continuous feed, in particular the bending process.

[0026] The bending unit can be moved along the process path by means of a feed motion on a closed path. For example, a closed guideway with one or more associated guides can be provided, along which one or more bending units are moved (forward). The closed path causes the bending unit to repeatedly pass through various stations of the process path as it travels along it, thus performing several bending operations. In one embodiment, it can be provided that after the wire contour is released from the bending unit, it is moved back into the receiving area to receive another wire section to be formed. Overall, this enables a continuous manufacturing process.

[0027] In a single pass along the path of travel, several wires can be drawn in either simultaneously or staggered in time and location, for example, by means of an upper and a lower bending section, each formed by one or more bending units that move along an upper and a lower path of travel. This allows the wire feed-in or drawing-in to be implemented at one location with multiple drums or at different locations.

[0028] One or more bending units can be moved or rotated along the process path at a constant speed.

[0029] The coil element can be manufactured as a wave winding for the coil winding of an electrical machine. Alternatively, the coil elements can be manufactured, for example, as a hairpin.

[0030] The embodiments described above in connection with the method for producing the wire contour for a coil element of a coil winding of an electrical machine can be provided accordingly in conjunction with the device for producing the wire contour for a coil element. Description of exemplary implementations

[0031] Further examples of implementation are explained in more detail below with reference to figures in a drawing. These show: Fig. 1 a schematic representation of a device for producing a wire contour for a coil element of a coil winding of an electrical machine from the front; Fig. 2 a schematic representation of the device from Fig. 1in top view; Fig. 3 a schematic representation of a section of a bending unit with forming elements for forming or bending a wire contour from a wire section and Fig. 4 a schematic representation of a wire contour for a coil element for a wave winding.

[0032] Fig. 1 and 2Figure 1 shows a schematic representation of a device for producing a wire contour for a coil element of a coil winding of an electric machine, from the front and in a top view. The device is designed to produce wire contours for coil elements in a continuous process, whereby the coil elements can be designed, for example, as a so-called hairpin or a wave winding. Such coil elements are also known in other embodiments. They are produced from wire sections by bending or forming and then fed into a further manufacturing process for producing a coil winding for the electric machine, as is known in various embodiments.

[0033] In the device according to the Fig. 1 and 2A wire reservoir 1 with wire reels 2 is provided to feed a wire 3 as continuous material to a process section 4. The process section 4 is formed with guide elements 5a, 5b, along which bending units 6, each with associated forming elements, can be moved by means of a feed motion. In the illustrated embodiment, the guide elements 5a, 5b of the process section 4 form a closed path of movement 7 for the bending units 6.

[0034] Along the process path 4, the bending units 6 are first brought into a receiving area 8, where a wire section 9, formed at the end of the wire 3, is received and clamped in the bending unit 6. Previously, the wire 3 was straightened in a straightening device 10. Additionally or alternatively, such pre-processing of the wire 3 can include checking the electrical insulation of the wire 3. Checking the wire geometry or contour can also be performed.

[0035] After the wire section 9 is inserted into or picked up by the bending unit 6, it is clamped in the bending unit 6. The bending unit 6 is designed to move forward along the process path 4 by means of a feed motion during the picking up and clamping of the wire section 9, either intermittently or continuously. In this way, the wire 3 is further unwound from the wire reel 2 and automatically drawn into the process path 4 by moving the bending unit 6 with the clamped wire section 9 forward along the process path 4. The wire section 9 being picked up and clamped is also thereby subjected to a wire tension that is maintained until clamping. By controlling the feed motion along the process path 4, the wire tension can be set to a predetermined value.

[0036] After clamping the wire section 9 in the bending unit 6, a bending or forming process is carried out in which the wire section 9 is formed into a wire contour in order to produce a coil element for the coil winding of an electrical machine, for example a hairpin element or a wave winding. For this bending process, the device according to Fig. 2The bending unit 6 is provided for in a section 11 of the process path 4 along the guide elements 5a, 5b, in which these are further apart from each other, i.e., diverge compared to the receiving area 8. This forces a bending movement onto the forming elements 12 of the bending unit 6 from the outside, which may in particular include a pivoting movement of the forming elements 12. This pivoting movement is performed with the forming elements 12 as a whole, in addition to the feed movement of the bending unit 6, in order to form the wire section 9 into the wire contour. In a subsequent section or area 13, this bending or forming movement is essentially completed, optionally including overbending, whereby the guide elements 5a, 5b are even further apart from each other here to effect the displacement of the forming elements 12.The wire contour thus formed is taken from the bending unit 6 into a subsequent discharge area 14 of the process section 4, whereby the clamp holding the wire contour on the bending unit 6 can be released. The wire contour produced in this way for the coil element can then be fed to further process steps downstream of discharge area 14.

[0037] The bending unit 6 travels along the process path 4 from the discharge area 14, along the guide elements 5a, 5b, back to the receiving area 8 by means of the driving feed motion, in order to receive another wire section to be formed. The movement of the bending units 6 along the guide elements 5a, 5b of the process path 4 can be continuous, whereby the speed of the feed motion can vary in individual sections of the process path 4 or remain constant throughout.

[0038] It can be provided that the feed of the bending unit 6 is continuous in the receiving area 8, in section 11 (which is formed in an intermediate area), in the subsequent section 13, and in the discharge area 14. Alternatively, it can be provided that the feed movement is (briefly) interrupted at one or more points along the process path 4, for example, when removing the wire contour from the bending unit 6 in the discharge area 14. Providing the feed movement for the bending units 6 along the process path 4, combined with the bending movement of the forming elements 12 of the bending unit 6 for forming the wire contour, enables a time-efficient, continuous process for producing the wire contours for coil elements.

[0039] The bending units 6 can be provided with associated form elements 12 in different configurations. While in the device in the Fig. 1 and 2If the forming elements 12 are displaced during the bending movement due to the changed spacing of the guide elements 5a, 5b in order to form the wire contour, an alternative design can be provided in which the displacement of the forming elements 12 is effected by means of separate drive means on the bending unit 6, i.e., not due to the movement forced from the outside by means of the guide elements 5a, 5b. Bending units with associated forming elements 12 are known as such in various embodiments and can be integrated into continuous process control.

[0040] Fig. 3 Figure 1 shows a schematic representation of a section of a bending unit 6 with forming elements 12 which, due to the changing distance between the guide elements 5a, 5b, perform the bending movement to form the wire contour. In this process, the forming elements 12 perform a pivoting movement such that they are displaced relative to each other.

[0041] Fig. 4 Figure 1 shows a schematic representation of a wire contour 20 produced in this way for a wave winding of an electrical machine.

Claims

1. Method for producing a wire contour for a coil element of a coil winding of an electrical machine, comprising: - providing a bending unit (6) with shaping elements (12) which can be displaced along a process path (4); - receiving and clamping a wire portion (9) in the bending unit (6) in a receiving region (8) along the process path (4); - carrying out a bending process in which the wire portion (9) is shaped by means of the shaping elements (12) of the bending unit (6) to form a wire contour for a coil element of a coil winding of an electrical machine; and - releasing the wire contour from the bending unit (6) in a dispensing region (14) which is arranged spaced apart from the receiving region (8) along the process path (4); wherein the bending process further comprises: - displacing the bending unit (6) with the shaping elements (12) by means of a feed movement between the receiving region (8) and the dispensing region (14), and - displacing the shaping elements (12) relative to one another by means of a bending movement in order to shape the wire portion (9) received in the bending unit (6) to form the wire contour, wherein the bending unit (6), after the release of the wire contour from the bending unit (6), is fed along the process path (4) by means of the feed movement to a further bending process in which a further wire portion (9) is bent by means of the shaping elements (12) of the bending unit (6) to form a further wire contour.

2. Method according to Claim 1, characterized in that the feed movement and the bending movement are carried out at least partially at the same time.

3. Method according to Claim 2, characterized in that the bending unit (6), during the relative displacement of the shaping elements (12) during the bending movement for shaping the wire portion, is displaced continuously by means of the feed movement along the process path (4).

4. Method according to Claim 1, characterized in that, during the relative displacement of the shaping elements (12) by means of the bending movement for shaping the wire portion (9), the bending unit (6) remains at least temporarily free of the feed movement in a rest position along the process path (4).

5. Method according to at least one of the preceding claims, characterized in that the bending unit (6), during the receiving and / or the clamping of the wire portion (9), is moved at least temporarily by means of the feed movement along the process path (4).

6. Method according to at least one of the preceding claims, characterized in that the bending unit (6), during the release of the wire contour from the bending unit (6), is moved at least temporarily by means of the feed movement along the process path (4).

7. Method according to at least one of the preceding claims, characterized in that a predetermined wire tensile stress is applied to the wire portion (9).

8. Method according to at least one of the preceding claims, characterized in that the wire portion (9) is premachined in the process path (4) before being received in the bending unit (6).

9. Method according to at least one of the preceding claims, characterized in that the wire portion (9) is separated from an endless wire supply before carrying out the bending process.

10. Method according to at least one of the preceding claims, characterized in that the wire portion (9) is fed to the bending unit (6) from a wire reservoir and, after the clamping of the wire portion (9) in the bending unit (6), a following wire portion (9) is drawn in from the wire reservoir and fed to a following bending unit (6) by means of the feed movement of the bending unit (6) along the process path (4).

11. Method according to at least one of the preceding claims, unless referring back to Claim 4, characterized in that the bending unit (6) is displaced continuously along the process path (4) by means of the feed movement.

12. Method according to at least one of the preceding claims, characterized in that the bending unit (6) is displaced along the process path (4) on a closed movement path by means of the feed movement.

13. Method according to at least one of the preceding claims, characterized in that the coil element is produced as a wave winding for a coil winding of an electrical machine.

14. Device for producing a wire contour for a coil element of a coil winding of an electrical machine, comprising: - a process path (4); - a bending unit (6) with shaping elements (12) and - a control and operating device which is assigned to the process path (4) and is configured, during bending operation, to displace the bending unit (6) by means of a feed movement along the process path (4) and further to control the following: - receiving and clamping a wire portion (9) in the bending unit (6) in a receiving region (8) along the process path (4); - carrying out a bending process in which the wire portion (9) is shaped by means of the shaping elements (12) of the bending unit (6) to form a wire contour for a coil element of a coil winding of an electrical machine; and - releasing the wire contour from the bending unit (6) in a dispensing region (14) which is arranged spaced apart from the receiving region (8) along the process path (4); wherein the bending process further comprises: - displacing the bending unit (6) with the shaping elements (12) by means of a feed movement between the receiving region (8) and the dispensing region (14), and - displacing the shaping elements (12) relative to one another by means of a bending movement in order to shape the wire portion (9) received in the bending unit (6) to form the wire contour, wherein the bending unit (6), after the release of the wire contour from the bending unit (6), is fed along the process path (4) by means of the feed movement to a further bending process in which a further wire portion (9) is bent by means of the shaping elements (12) of the bending unit (6) to form a further wire contour.

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