Device and method for winding wave windings, forming jaw, and forming pliers

Abstract

The invention relates to a device (1) for winding wave windings for stators or rotors of electric machines, comprising a winding blade (10), which can be rotated about an axis of rotation (12) by means of a drive device (3); a wire feed (16), by means of which wires (14) can be fed to the winding blade (10) perpendicularly to the axis of rotation (12) of the winding blade; and forming jaws (24, 26), which are provided on forming pliers (22) and can be moved towards one another and by means of which a post-forming process can be carried out on the winding heads (20) of the wave winding by the winding blade (10), each of the forming jaws (24, 26) having a press strip (9) which can be contacted by the wires (14) wound on the winding blade (10), the press strip (9) being pivotally mounted on the respective forming jaw (24, 26).

Description

[0001] Device and method for winding wave windings, forming jaw and forming tongs

[0002] The present invention relates to a device and a method for winding shaft windings for stators or rotors of electrical machines, comprising a winding blade rotatable about a rotational axis by means of a drive device, a wire feed through which wires can be fed to the winding blade perpendicular to the rotational axis, and forming jaws arranged on a forming tool and movable towards each other by means of which the winding heads of the shaft winding can be reshaped on the winding blade. The invention further relates to a forming jaw and a forming tool.

[0003] In connection with devices for winding shaft windings for stators or rotors of electrical machines, it is known that problems frequently arise during the production of winding mats made from flat wire. These problems relate to both the wire feed and the forming and stabilization of the winding mats during the winding process.

[0004] During the production of winding mats, variations in wire cross-section and insulation thickness within permissible tolerances often lead to wire jamming in the wire feed. These variations prevent the wires from being fed evenly, resulting in disruptions in the winding process and increased scrap.

[0005] Furthermore, the winding mat must be pre-formed during the winding process to prevent twisting when removed from the machine. However, this pre-forming is difficult to control, especially if the wire feed and the forming device are not optimally matched.

[0006] Furthermore, the winding mat can often only be shaped or held in a defined position because the winding blade has different angular positions. This means that either the winding mat can be held to prevent the wires from being pulled along, or it can be shaped. A combination of holding and shaping is not possible with current technology.

[0007] To hold the winding mat, forming jaws with a pre-made angle of 172° or 8° are required, while forming jaws with angles of 178° or 2° are needed for shaping. If the angles of the forming jaws and the winding blade are not precisely matched, pressure marks will appear on the insulation or wire will be damaged, resulting in an unacceptable product (rejection).

[0008] Current technology does not allow for a flexible combination of holding and forming, as the forming jaws and the winding blade operate at different angular positions. This leads to inefficient and error-prone production of winding mats.

[0009] The device described in DE 10 2022 120 094 A1 attempts to address some of these problems by employing a method and a device for forming wave windings using a flat template (winding blade) that can be rotated about its longitudinal axis. A number of parallel wires are fed by a wire feeder perpendicular to the template's axis of rotation and wound around it by incrementally rotating the template. During the winding process, the wire feeder follows the wires into the area of ​​the template. To improve the quality of the winding heads, the template is first rotated by less than 180 degrees, and the partially formed winding heads are reshaped using forming jaws. The wire feeder is then retracted, and the template is rotated further to 180 degrees to finalize the winding heads.

[0010] Despite these approaches, some technical challenges remain, such as the need to retract the wire feed and operate the forming jaws at specific angular positions, resulting in a complex process. It is therefore the object of the present invention to avoid or at least mitigate these problems and to provide improved coordination of the holding and forming processes in order to enable more efficient and higher-quality production of winding mats.

[0011] This problem is solved by a device for winding shaft windings for stators or rotors of electrical machines, comprising a winding blade which is rotatable about a rotary axis by means of a drive device and a wire feed through which wires can be fed to the winding blade perpendicular to the rotary axis of the winding blade, and forming jaws arranged on a forming pliers and movable towards each other by means of which the winding heads of the shaft winding can be reshaped on the winding blade, wherein the forming jaws each have a pressure bar that can be contacted with the wires wound on the winding blade, wherein the pressure bar is pivotably mounted on the respective forming jaw.

[0012] This device offers the advantage that the pivoting mounting of the pressure bars on the forming jaws allows for more flexible and precise reshaping of the winding heads. The pivoting pressure bars allow for adaptation to varying wire geometries and positions during the winding process, thus reducing the risk of wire damage and pressure marks on the insulation layer. Furthermore, the forming tool can be configured to both hold and shape the winding mats at different rotational angles of the winding blade. This results in higher quality end products and significantly reduces the reject rate. In addition, the pivoting mounting of the pressure bars eliminates the need for tool changes, thereby reducing overall process time.

[0013] For the purposes of this patent application, a forming tool is a tool used in a device for winding shaft windings for stators or rotors of electrical machines. The forming tool comprises forming jaws that can be moved towards each other to allow the winding heads to be reshaped on a winding bar. The function of the forming tool is therefore essentially to bring the winding heads of the shaft winding, produced during the winding process, into the desired shape and hold them in that position. The use of the forming tool ensures that the winding heads are formed precisely, thereby improving the quality and performance of the manufactured windings. The forming tool makes it possible to hold the wires in place during the winding process while simultaneously reshaping the winding heads at various rotational angles of the winding bar.

[0014] The forming tool comprises several components. Central to the design are the forming jaws, each featuring a pressure bar that comes into contact with the wires wound on the winding bar. The pressure bars are pivotally mounted on the forming jaws, allowing for flexible adjustment to different wire geometries and positions. The forming jaws themselves are attached to the forming tool in such a way that they can be moved towards and away from each other to reshape the winding heads. Preferably, a drive mechanism provides the necessary movement of the forming jaws.

[0015] A preferred embodiment features a stationary forming jaw, which ensures stable and repeatable positioning during the winding and forming process. This increases the accuracy and consistency of the wire feeding and forming. Another possible embodiment includes a movable forming jaw, which allows the forming jaws to be operated in different positions and angles to achieve greater flexibility in forming.

[0016] Preferably, the pressing bars of the forming jaws are aligned parallel to each other to ensure even pressure distribution during the forming process. The pendulum mounting of the pressing bars achieves high adaptability and flexibility of the forming tool, further improving the quality and precision of the forming process.

[0017] For the purposes of this patent application, a forming jaw is a component of a forming tool used to shape and hold the winding heads of shaft windings for stators or rotors of electrical machines. A forming jaw is used to exert precise pressure on the wound wires to bring them into the desired shape and simultaneously hold them in place.

[0018] A key function of the forming jaw is therefore to hold and reshape the winding heads during the winding process. This is achieved by applying even pressure to the wires, thus enabling the winding heads to be fixed and precisely shaped. The forming jaws advantageously work together in pairs to shape the wire evenly from both sides.

[0019] Another embodiment could include forming jaws equipped with sensors and actuators to enable automatic adaptation to different wire geometries and winding requirements, further increasing the efficiency and precision of the winding process.

[0020] The structure of a forming jaw advantageously comprises a base body, a pressure bar and a pivot bearing.

[0021] The base body of the forming jaw ensures its structural integrity and stability. This base body can be made of robust materials such as hardened steel or a high-strength aluminum alloy. The pressure bar is attached to the forming jaw and pivotally mounted. The pressure bar is the element that makes direct contact with the wires and applies pressure to form the winding heads. The pressure bar can be made of a material that exhibits both high strength and low friction, such as hardened steel or a specially coated metal. Pressure bars can be provided with special coatings that minimize friction and increase the service life of the forming jaw. Such coatings could consist of materials such as Teflon or other friction-reducing substances.The swivel bearing allows the press bar to move, enabling it to adapt flexibly to the wire geometries. This swivel bearing allows the press bar to be pivoted at various angles to ensure optimal shaping.

[0022] For the purposes of this patent application, the pivot bearing is a special mechanical device that allows the pressing bar of a forming jaw to pivot about a defined axis. This helps to adapt the pressing bar flexibly and precisely to the geometry of the wound wires.

[0023] The swivel bearing advantageously includes components such as a bearing housing, a bearing shaft, a bearing bushing or a ball bearing.

[0024] The bearing housing can be formed in one piece, particularly monolithically, with the mold jaw or the base body of the mold jaw. The housing of the swivel bearing, which is attached to or formed with the mold jaw, accommodates the bearing shaft of the bearing. It provides the necessary structural support and ensures the correct alignment of the swivel axis or the bearing shaft.

[0025] The bearing shaft is the central axis around which the pressure bar can be pivoted. The bearing shaft is connected to the pressure bar, so pivoting the bearing shaft causes the pressure bar to pivot as well.

[0026] The bearing shaft is preferably supported in at least one bearing bushing or at least one ball bearing. The at least one bearing bushing is preferably arranged in the mold jaw or the base body of the mold jaw. It is also preferred that the outer ring of the ball bearing is rotationally fixed in the mold jaw or the base body of the mold jaw.

[0027] Additionally, damping elements can be provided in the swivel bearing, such as elastic components like springs or rubber buffers, which absorb shocks and vibrations during the winding process and ensure smooth movement of the press bar.

[0028] Advantageous embodiments of the invention

[0029] According to an advantageous embodiment of the invention, the pressure bars are each arranged on one of the forming jaws by means of a pivot bearing, the pivot bearings being configured such that the stationary forming jaw can be held in a closed operating state between a rotational angular position of the winding blade of 170-180°, preferably 172-178°. This embodiment offers the advantage that the pivot bearings of the pressure bars enable precise control of the forming jaw at specific rotational angular positions of the winding blade. In particular, the stationary forming jaw can be held in a closed operating state at a rotational angle of 170-180°, preferably 172-178°. This ensures consistent and repeatable positioning of the winding mat during post-forming, thereby increasing the accuracy of the forming process.The ability to hold the forming pliers in a fixed position also helps to better control tolerances in wire feeding and forming, leading to improved process stability and product quality. Additionally, precise control of the rotation angle optimizes the integration of the holding and forming process, reducing the need for additional tools and work steps.

[0030] The object of the invention is also achieved by a forming jaw, particularly for use in a forming tool of a device for winding shaft windings for stators or rotors of electrical machines, wherein the forming jaw has a pressure bar that can be contacted with the wires wound on the winding blade, and wherein the pressure bar is pivotably mounted on the forming jaw. The pivotable mounting of the pressure bar on the forming jaw enables improved adaptability to the wire geometries and positions. This results in a more uniform distribution of the pressure forces during the forming process and reduces the risk of damage to the wire insulation. The pivotable pressure bar can flexibly adapt to the winding heads, thereby achieving more precise forming. This advantage is particularly important for ensuring high quality of the winding mats and minimizing the reject rate.The swiveling bearing also facilitates the use of the forming jaw in different positions and applications, which increases the versatility and efficiency of the winding process.

[0031] Furthermore, the object of the invention can be achieved by a forming tool for use in a device for winding shaft windings for stators or rotors of electrical machines, comprising forming jaws according to claim 3. The use of the described forming jaws in a forming tool offers the advantage that the forming tool is versatile and adaptable. Due to the pivotable pressing bars on the forming jaws, the forming tool can react precisely and flexibly to different wire geometries and winding configurations. This enables high accuracy in reshaping the winding heads and significantly reduces the risk of wire damage. The forming tool can be used both for holding and forming the winding mats, which simplifies the process steps and reduces cycle time. The stationary design of the forming tool further contributes to the stability and repeatability of the winding process.

[0032] Furthermore, the object of the invention can be achieved by a method for winding shaft windings for stators or rotors of electrical machines, comprising the following steps:

[0033] Provision of a winding blade that can be rotated about a rotary axis by means of a drive device;

[0034] Provision of a wire feed through which wires can be fed to the winding blade perpendicular to its axis of rotation;

[0035] Provision of a forming tool with forming jaws arranged on it and movable towards each other, by means of which the winding heads of the wave winding can be reshaped on the winding bar, wherein the forming jaws each have a pressure bar that can be contacted with the wires wound on the winding bar and which is pivotably mounted on the respective forming jaw; a) Feeding a plurality of parallel wires through the wire feed perpendicular to the axis of rotation of the winding bar, wherein the wires are alternately wound around it by stepwise rotation of the winding bar and formed into a wave winding by intermediate lateral displacement relative to the wires already lying on the winding bar, wherein during winding the wires the wire feed follows the wires into the area of ​​the winding bar; b) Rotation of the winding bar by less than 180 degrees during winding of the wires;c) Reshaping the partially formed winding heads in an intermediate step using the forming jaws; d) Retracting the wire feed from the area of ​​the winding bar; wherein steps cd can be carried out in any order; e) Further rotating the winding bar to final forming the winding heads to the degree, wherein at least steps cd are carried out with the forming pliers closed.

[0036] This method offers the advantage of a systematic and efficient approach to winding shaft windings. The provision and use of a rotating winding bar and a wire feed that follows the wires into the area of ​​the winding bar ensures precise and consistent wire feeding. The combination of steps for rotating the winding bar, reshaping the winding heads, and retracting the wire feed optimizes the winding process by increasing flexibility and reducing process time. The use of pivoting press bars on the forming jaws enables precise shaping and minimizes the risk of wire damage. Performing steps c) to e) with the forming jaws closed further increases the stability of the process.

[0037] Furthermore, the invention can also be further developed in such a way that the wire feed is withdrawn from the area of ​​the winding blade at a rotation angle position of the winding blade of 170-175°, preferably 172°.

[0038] This precise control of the wire feed ensures that the wires are always optimally positioned during the winding process, resulting in a more even and consistent winding. This reduces the risk of wire jamming and increases the overall quality of the winding mats. The fixed rotation angle position also contributes to the synchronization of the various process steps, which increases the efficiency of the process and reduces cycle time.

[0039] In a further preferred embodiment of the invention, the forming of the winding heads can also be carried out by means of the forming jaws at a rotational angle of the winding blade of 175-180°, preferably 178°. This offers the advantage that the forming process is carried out at an optimal angle, enabling precise adaptation to the wire geometries. The precise control of the rotational angle allows the forming jaws to be held in an optimal position, which increases the efficiency and accuracy of the forming process.

[0040] It can also be advantageous to further develop the invention such that the pressing bars of the forming jaws are always aligned parallel to each other. The consistently parallel alignment of the pressing bars of the forming jaws offers the advantage that the pressing forces are distributed evenly across the wires during the forming process. This leads to more consistent forming and significantly reduces the risk of wire damage. According to a further preferred embodiment of the invention, the forming pliers can be designed to be stationary in process steps c) and d), which ensures stable and repeatable positioning during the winding and forming process. This increases the accuracy and consistency of the wire feeding and forming, resulting in higher quality of the winding mats.The stationary forming tool also reduces the need for complex motion controls, improving the reliability and ease of maintenance of the device. Furthermore, the stationary design contributes to process stability by minimizing vibrations and mechanical stresses that could affect the quality of the winding mats.

[0041] The invention will now be explained in more detail with reference to figures, without limiting the general concept of the invention.

[0042] It shows:

[0043] Figure 1 shows a schematic sequence of a partial winding process according to the state of the art.

[0044] Figure 2 shows a schematic representation of a device 1 according to the invention for winding shaft windings for stators or rotors of electrical machines.

[0045] Figure 3 shows a schematic sequence of a partial winding process using the device known from Figure 2.

[0046] Figure 4 shows a detailed view of the die jaws in a first operating position,

[0047] Figure 5 shows a detailed view of the forming jaws in a second operating position. Figure 1 shows the previously standard sequence of a partial winding operation for producing a flat wave winding using a winding blade 10, which is rotatably mounted about a pivot axis 12 and is rotated stepwise by means of a drive device 3 to wind a plurality of wires 14, of which only one wire 14 is shown, onto the winding blade 10. Between the partial winding operations, an axial displacement / deformation of the wires 14 occurs, so that the wave winding is ultimately ribbon-shaped. The wires 14 are fed and stabilized by means of a wire feeder 16.

[0048] A partial winding operation is carried out by rotating the winding blade 10 by slightly less than 180 degrees, after the wires 14 in front of the winding blade 10 have been shifted laterally relative to the wires 14 lying on the winding blade 10. The center of the resulting inclined transition area lies in the region of a bending edge 18 of the winding blade 10. The transition area is created by axial displacement (with respect to the longitudinal extent of the winding blade 10) between the wire feed 16 and a clamping device (not shown) provided on the winding blade 10. This is known and can also be implemented accordingly within the scope of the present invention.

[0049] Starting from the state shown in Fig. 1 a), the winding blade 10 is now rotated counterclockwise in the direction shown in the illustration, with Fig. 1 b) showing an intermediate position at a 90-degree angle of rotation. The wire feed 16 following the wire 14, which prevents deformation of the transition area required for forming the roof shape of the winding heads 20, is clearly visible in Fig. 1 b).

[0050] Figure 1c shows a state in which the rotation of the winding blade 10 must first be stopped at approximately 175 degrees because the wire feed 16 would collide with the winding blade 10 at a collision point K if it were to continue rotating. Depending on the geometry, the angle may vary. However, a 180-degree bend is impossible. In a further step, the wire feed 16 must be retracted (see Figure 1d)) before the winding blade 10 can complete half a turn for this partial winding step. At this point, the wires 14 are no longer fixed near the bending edge 18, so they can no longer be plastically deformed. Elastic stresses remain in the wire 14, which accumulate as the winding progresses and complicate further processing of the wave winding after it is removed from the winding blade 10.Furthermore, the removal of the wire feed 16 can lead to a deformation of the winding heads 20 due to frictional forces introduced into the wires 14.

[0051] Figures 2-5 show a device according to the invention which, compared to the prior art, is supplemented by a forming clamp 22 with two forming jaws 24, 26, which is movable in the engagement area with the winding blade 10. The forming jaws 24, 26 each have a pressing bar 9 that can be contacted with the wires 14 wound on the winding blade 10, and the pressing bar 9 is pivotably mounted on the respective forming jaw 24, 26. The forming jaws 24, 26 are thus rotatably mounted via pivot bearings 4a, 4b, which are formed on a base body 5c, 5b.

[0052] A device enables the forming jaws 22 to be moved between the position shown in Fig. 5, in which the previously produced winding heads 20 can be reshaped by pressing the forming jaws 24, 26 together, and a retracted position in which the winding blade 10 is freely rotatable during the partial winding operations.

[0053] Fig. 2 shows a manufacturing step of the inventive method using the device shown in detail in Figures 4-5.

[0054] Before the wire feed 16 is retracted, the forming pliers 22 are brought into the engagement area with the previously wound wires 14, and the forming jaws 24, 26 are closed. During this process, the wires 14 are reshaped, and in particular, they are bent further in the direction of the 180-degree bend in the area of ​​the bending edge 18. Only after this reshaping is the wire feed 16 removed, with the forming jaws 24, 26 remaining closed, so that any frictional forces acting on the wires 14 during the removal of the wire feed 16 cannot deform the winding heads 20.

[0055] After removing the wire feed 16, the forming pliers 22 are opened and retracted, whereby the deformation produced in the engagement area of ​​the forming jaws 24, 26 is not visible in the illustration.

[0056] Figures 4-5 show in detail a forming tool 22 with forming jaws 24, 26 arranged on it and movable towards each other, by means of which the winding heads 20 of the shaft winding can be reshaped on the winding bar 10. The pressure bars 9a, 9b are each arranged on one of the forming jaws 24, 26 by means of a pivot bearing 4, the pivot bearings 4 being configured such that the forming tool 22 can be held in a closed operating position between a rotational angular position of the winding bar 10 of 172-178° during the operating conditions shown in Figures 4-5.

[0057] Figure 4 shows the angular position of the winding blade 10 at 172°, as set when the wire feed 16 is retracted. Figure 5 shows the angular position of the winding blade 10 at 178°, which is assumed when forming the winding head 20. It can be clearly seen that the forming jaws 24, 26 can compensate for this angular difference, and that the pressure bars 9a, 9b are always in contact with the wires 14.

[0058] The wire feed 16 is withdrawn from the area of ​​the winding blade 10 when the winding blade 10 is rotated at 172°, while the winding heads 20 are reshaped by the forming jaws 24, 26 when the winding blade 10 is rotated at 178°. The pressing bars 9a, 9b of the forming jaws 24, 26 are always aligned parallel to each other. The forming pliers 22 remain stationary during these process steps of withdrawing the wire feed 16 and reshaping the winding heads 20.

[0059] The invention is not limited to the embodiments illustrated in the figures. The foregoing description is therefore not to be considered limiting, but rather explanatory. The following claims are to be understood as meaning that a named feature is present in at least one embodiment of the invention. This does not preclude the presence of further features. Where the claims and the foregoing description define 'first' and 'second' features, this designation serves to distinguish between two similar features without establishing any hierarchy.

[0060] List of reference signs

[0061] 1 Device

[0062] 3 Drive unit

[0063] 4 Swivel bearing

[0064] 5 basic shapes

[0065] 9 Press bar

[0066] 10 Winding sword

[0067] 12 Rotation axis

[0068] 14 wires

[0069] 16 Wire feed

[0070] 18 Bending edge

[0071] 20 winding heads

[0072] 22 Forming pliers

[0073] Bake in a 24-piece mold

[0074] Bake in 26 pans

Claims

Claims 1. Device (1) for winding shaft windings for stators or rotors of electrical machines, comprising a winding blade (10) which is rotatable about a rotational axis (12) by means of a drive device (3) and a wire feed (16) through which wires (14) can be fed to the winding blade (10) perpendicular to the rotational axis (12) of the winding blade (10), and forming jaws (24, 26) arranged on a forming pliers (22) and movable towards each other, by means of which the winding heads (20) of the shaft winding can be reshaped on the winding blade (10), characterized in that the forming jaws (24, 26) each have a pressure bar (9) that can be contacted with the wires (14) wound on the winding blade (10), wherein the pressure bar (9) is pivotably mounted on the respective forming jaw (24, 26).

2. Device (1) according to claim 1, characterized in that the pressure bars (9) are each arranged on one of the forming jaws (24, 26) by means of a pivot bearing (4), wherein the pivot bearings (4) are configured such that the stationary forming jaw (22) can be held in a closed operating state between a rotation angle position of the winding blade (10) of 170-180°, preferably 172-178°.

3. Forming jaw (24, 26), in particular for use in a forming pliers (22) of a device (1) for winding shaft windings for stators or rotors of electrical machines, characterized in that the forming jaw (24,26) has a pressure bar (9) that can be contacted with the wires (14) wound on the winding blade (10), wherein the pressure bar (9) is pivotably mounted on the forming jaw (24,26).

4. Forming pliers (22) for use in a device (1) for winding shaft windings for stators or rotors of electrical machines, comprising forming jaws (24, 26) according to claim 3.

5. Method for winding shaft windings for stators or rotors of electrical machines, comprising the following steps: Provision of a winding blade (10) which can be rotated about a rotary axis (12) by means of a drive device (3); Provision of a wire feed (16) through which wires (14) can be fed to the winding blade (10) perpendicular to the axis of rotation (12); Provision of a forming tool (22) with forming jaws (24, 26) arranged on it and movable towards each other, by means of which the winding heads (20) of the wave winding can be reshaped on the winding blade (10), wherein the forming jaws (24, 26) each have a pressure bar (9) that can be contacted with the wires (14) wound on the winding blade (10) and which is pivotably mounted on the respective forming jaw (24, 26); a) Feeding a plurality of parallel wires (14) through the wire feed (16) perpendicular to the axis of rotation of the winding blade (10), wherein the wires (14) are alternately wound around the winding blade (10) by stepwise rotation and by intermediate - 19 - laterally offset relative to the wires (14) already lying on the winding blade (10) to form a wave winding, wherein, during winding the wires (14), the wire feed (16) follows the wires (14) into the area of ​​the winding blade (10); b) rotating the winding blade (10) during winding the wires (14) initially by less than 180 degrees; c) reshaping in an intermediate step of the partially formed winding heads (20) by means of the forming jaws (24, 26); d) retracting the wire feed (16) from the area of ​​the winding blade (10); wherein steps c)-d) can be carried out in any order; e) further rotating the winding blade (10) to the final shaping of the winding heads (20) to 180 degrees, wherein at least steps c)-d) are carried out with the forming pliers (22) closed.

6. Method according to claim 5, characterized in that the retraction of the wire feed (16) from the area of ​​the winding blade (10) takes place at a rotation angle position of the winding blade (10) of 170-175°, preferably 172°.

7. Method according to claim 5 or 6, characterized in that - 20 - the reshaping of the winding heads (20) by means of the forming jaws (24, 26) at a rotation angle position of the winding blade (10) of 175-180°, preferably 178°, is carried out.

8. Method according to one of claims 5-7, characterized in that the press bars (9) of the forming jaws (24,26) are always aligned parallel to each other.

9. Method according to one of claims 5-8, characterized in that the forming pliers (22) are designed to be stationary in process steps c) and d).

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