Method and device for shaping wave winding

Abstract

The invention relates to a method for forming a product by means of a flat former (10; 110), in which a plurality of parallel wires (14) are brought into contact with a former (10; 110), in which the wire (14) is fed perpendicular to the axis of rotation of the former (10; the invention relates to a method for forming a wave winding (100) by winding a wire (14) on a former (10) by means of a step-by-step rotation (110, 110) alternately and forming the wire into the wave winding (100) by means of a lateral offset between said step-by-step rotation with respect to the wire (14) that has been positioned on the former, in which a wire feeder (16) follows the wire as the wire (14) is wound until into the region of the former (10). In order to be able to produce wave windings which have a small tension and thus can be better processed further, it is proposed that the former (10) is first rotated by less than 180 degrees when the wire (14) is wound, and in an intermediate step by means of the forming jaws (24, 26; according to the invention, the winding head (20), which has just been partially shaped, is reshaped by means of the wire feeder (16), then the wire feeder (16) is withdrawn from the region of the former (10), and finally the former (10) is rotated to 180 degrees for the final shaping of the winding head (20).

Description

Technical Field

[0001] According to the preamble, the invention relates to a method for forming a wave winding by means of a flat former rotatable about its longitudinal axis, wherein a plurality of parallel wires are fed perpendicularly to the axis of rotation of the former by means of a wire feeder, wherein the wires are alternately wound around the former by rotating the former stepwise through 180 degrees and the wires are formed into a wave winding by means of a lateral offset relative to the already wound wires between the stepwise rotations, wherein the wire feeder follows the wire as it is wound until it enters the region of the former. The invention also relates to a device having the features of the preamble of claim 7. Background Art

[0002] Such a method and the associated device are known, for example, from DE 10 2015 120 661 A1. It has been shown that problems may arise when implementing this method, since during winding, the wire feeder protrudes into the region of the former and the winding process therefore cannot achieve the ideal state of gradually rotating the former by 180 degrees, but must be stopped at an intermediate stage of less than 180 degrees. Incomplete bending of the winding head generates tensions in the wire, which accumulate as the winding progresses and make subsequent processing more difficult, since the wave winding must be transferred into the stator slots, which may be done in an intermediate step with the aid of a slotted tool. Summary of the invention

[0003] The object of the invention is to enable better shaping of the winding head during the manufacturing process of the wave winding.

[0004] According to the invention, this object is achieved by a type of the type mentioned at the outset, in which, when the wire is wound, the former is first rotated less than 180 degrees, the winding head that has just been partially formed is reshaped by the forming jaws in an intermediate step, the wire feeder is then withdrawn from the area of ​​the former, and the former is finally rotated to 180 degrees for the final shaping of the winding head.

[0005] The solution according to the invention provides the following advantages: the wire is fixed and optionally reshaped at a position where the former has not yet rotated a full 180 degrees. This angular position corresponds to the maximum value that can be achieved so far, and if the former continues to rotate, the wire feeder that is required to stabilize the wire during the bending process will collide with the rotating former. Therefore, reshaping will then cause the wire to be bent to a position of 180 degrees or beyond the half positioned on the lower side of the former relative to the winding head. Therefore, the head is fully formed and no tension is built up during the winding process due to incomplete bending.

[0006] After the wire feeder has been removed, the former can be further rotated into a final position of up to 180 degrees and then the forming step is carried out in an axial direction with respect to the longitudinal extension of the former.

[0007] In a preferred development of the method, it is provided that the forming jaws remain closed until the wire feeder is removed. This prevents the friction forces acting on the wire from the wire feeder from deforming the winding head in an undesirable manner.

[0008] In order to prevent the forming jaw from obstructing the winding process itself, it is provided that the forming jaw is brought into the region of engagement with the wire only for the duration of the forming process.

[0009] In another particularly preferred embodiment of the method, it is provided that the re-forming is performed with the aid of a single-sided recess or two congruent recesses on both sides in the former and correspondingly shaped forming jaws, so that the wire is initially bent more than 180 degrees relative to the wire position on the other side of the former.

[0010] This variant takes into account the fact that the wire, when bent around the edge of the former, not only deforms plastically, but also always has an elastic deformation component, by which it springs back or remains as a kind of spring tension in the winding. Overbending during re-forming compensates for this elastic deformation component; after the forming jaws are removed, the wire can spring back to the ideal position of 180 degrees.

[0011] Typically, this process will require the former to be rotated to a certain angle before re-forming, at which the wire guide just does not contact the former, but deviations may occur. Typically, it is provided that the former is rotated about 175 degrees before re-forming.

[0012] The invention also relates to a device for winding a wave winding from a plurality of wires fed in parallel by means of wire guides, the wires initially extending perpendicularly to the axis of rotation of a flat sword-shaped former which can be rotated stepwise by means of a drive, and to a device for reshaping the winding head. In order to achieve the above-mentioned purpose of producing wave windings with higher quality, it is provided that the device for reshaping the winding head includes a forming jaw for reshaping the winding head, wherein the pair of forming jaws are held on a movable device, and after the winding process is interrupted before a 180-degree rotation is achieved, the movable device brings the forming jaws into the area of ​​the winding head and there clamps the finally produced winding head against the former and reshapes it, and the movable device removes the forming jaws from the rotation area of ​​the former again after the wire feeder is retracted and the pair of forming jaws are released and before the drive device completes the rotation process up to 180 degrees, wherein the movement of the drive device, the wire feeder and the movable device is coordinated by means of a control device.

[0013] According to the invention, means for reshaping the winding heads in the above-described manner are incorporated into the device and its operating sequence. Other types of reshaping devices known from the prior art can be omitted, and the windings produced with the device according to the invention are less tensile and more dimensionally stable, so that these windings can be better handled in subsequent processes.

[0014] Preferably, it is provided that the control device interrupts the winding process before the wire feeder contacts the former and the reshaping process of the winding head produced last is carried out in a rotation angle position of the former of about 175 degrees so that the forming jaws are formed on the forming clamp.

[0015] Particularly preferred is an embodiment of the device in which the former has a recess in the region of the winding head on one or both sides which, in cooperation with the correspondingly shaped forming jaws, enables the wire guide to be bent by more than 180 degrees. The advantages of overbending the wire that can be achieved by means of a device of this type have already been discussed above in conjunction with the description of preferred embodiments of the method. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Further features, details and advantages of the invention emerge from the wording of the claims and from the exemplary embodiments described below with reference to the accompanying drawings. In the drawings:

[0017] Figure 1 Figures a) to d) in the drawings show a schematic sequence of a partial winding process according to the prior art;

[0018] Figure 2A schematic plan view of a single wire of a winding head is shown;

[0019] Figure 3 shows the conventional partial winding process after Figure 2 A side view of the winding head in FIG.

[0020] Figure 4 Details of the bending points of the wire are shown;

[0021] Figure 5 A device according to the invention is shown;

[0022] Figure 6 Figures a) to f) in the drawings show a schematic sequence of a partial winding process according to the present invention;

[0023] Figure 7 shows a side view of a preferred embodiment of the winding device;

[0024] Figure 8 Shows Figure 7 Enlarged detail in Figure X. DETAILED DESCRIPTION

[0025] Figure 1 The usual sequence of partial winding processes in the production of a flat wave winding 20 by means of a flat sword-shaped former 10 is shown, which is mounted so as to be rotatable about an axis of rotation 12 and is rotated stepwise by means of a drive device (not shown) so as to wind a plurality of wires (only one wire 14 of the plurality of wires is shown) on the former 10. In this case, an axial displacement / deformation of the wire occurs between the partial winding processes, so that the wave winding is in the form of a strip at the end. The wire 14 is fed and stabilized by means of a wire feeder 16.

[0026] The partial winding process is performed by rotating the former 10 slightly less than 180 degrees after the wire in front of the former is moved laterally relative to the wire located on the former. The center of the resulting inclined transition area is located in the area of ​​the bent edge 18 of the former 10. The transition area is generated by an axial displacement (relative to the longitudinal extension of the former 10) between the wire feeder and the clamping device (not shown) arranged on the former 10. This is known and can also be implemented accordingly within the scope of the invention.

[0027] from Figure 1 Starting from the state shown in Figure a), the former now rotates counterclockwise in the direction shown, wherein Figure 1 Figure b) in FIG. 1 shows an intermediate position at a rotation angle of 90 degrees. Figure 1The figure b) in FIG. 1 clearly shows that the wire feeder 16 follows the wire to prevent deformation in the transition area, which is necessary to form the roof-shaped winding head (see also Figure 2 ).

[0028] Now, Figure 1 Figure c) in FIG shows a state in which the rotation of the former must first be stopped at about 175 degrees, because if the former continues to rotate, the wire feeder 16 will collide with the former 10 at the collision point K. This angle can vary depending on the geometry. However, a bend of 180 degrees is not possible.

[0029] In another step, the wire feeder 16 must now rotate half a turn in which the former can complete the partial winding step (see Figure 1 e)) before retracting (see Figure 1 d) in FIG. 1). However, the wire is no longer fixed near the bending edge 18, so that the wire can no longer be plastically deformed. An elastic tension remains in the wire, which accumulates as the winding process progresses and makes further processing of the wave winding more difficult after removal from the former 10. In addition, the removal of the wire feeder 16 may cause deformation of the winding head due to the friction introduced into the wire.

[0030] exist Figures 2 to 4 , the winding head region 20 produced after such a partial winding process is shown. Figure 2 The shape of the winding head is shown, wherein this shape is achieved via a transition region and is completed by bending around a bending edge 18. Figure 3 It is clear to see the shape that the wire takes when it is tension-free. However, due to the subsequent further rotation of the winding head, tension remains in the wire. Figure 4 The bending of the wire is illustrated in detail. The bending degree B1 that can be achieved by previous practice is shown to be about 175°, while the theoretical ideal bending state B2 of up to 180° required for the subsequent process is shown next to it. An overbending area B3 is shown adjacent to this ideal area, which will be necessary to take into account the springback in the wire.

[0031] Figure 5 The device according to the invention is shown which, in contrast to the prior art, is supplemented by a forming clamp 22 with two forming jaws 24, 26 which can be moved into the region of engagement with the former 10. All other parts of this simple embodiment correspond to the prior art. The device enables the forming clamp 22 to be able to Figure 5 The position shown is different from the retracted position (see Figure 6a), e) and f) in which position the previously produced winding head can be reshaped by pressing the forming jaws 24, 26 together, and in the retracted position the former can rotate freely during the partial winding process.

[0032] Figure 6 The use of the invention is shown Figure 5 The steps of the method of the device are shown.

[0033] Figure 6 Figure a) in FIG. 1 shows a different sequence compared to the prior art, which corresponds in principle to the Figure 1 c) in the figure, at this time, the rotation of the former 10 for bending the wire 14 must be stopped to avoid collision between the wire feeder 16 and the former.

[0034] Unlike the prior art, before the wire feeder 16 is retracted, the forming clamp 22 is brought into the area of ​​engagement with the previously wound wire and the forming jaws 24, 26 are closed. Here, the wire 14 is reshaped and, in particular, the wire 14 in the area of ​​the bending edge 18 is further bent in the direction of the 180-degree bend. Only after this reshaping is the wire feeder 16 removed, wherein the forming jaws 24, 26 remain closed so that during the removal of the wire feeder 16, any friction forces acting on the wire 14 do not deform the winding head.

[0035] After the wire feeder 16 has been removed, the forming jaws 22 are opened and retracted, wherein the deformations produced in the joining region of the forming jaws 24 , 26 are not visible in the illustration.

[0036] Since the wire 14 always also has an elastic deformation component, which manifests itself as a springback of the wire or a tension remaining in the wire after the removal of the forming tool, Figure 7 and Figure 8 The embodiment of the device shown provides a former 110 which has a recess 30 or a gap in the region of the winding head in the reshaping region, which interacts with correspondingly shaped forming jaws 124, 126. Since the wire can be bent into the recess 30, the total bending angle in the region of the bending edge 18 is greater than 180 degrees. This can be described as an overbending of the wire 14. After the forming jaws 124, 126 are removed, the wire can then spring back to the tension-free state with the ideal bending angle of 180 degrees, so that the resulting wave winding has less tension overall and can then be better processed.

[0037] All features and advantages arising from the claims and the description, including structural details, spatial arrangements and method steps, may be essential to the invention, both individually and in any combination.

[0038] Reference numerals list

[0039] 10, 110 former

[0040] 12 Axis of rotation of the former

[0041] 14 Wire

[0042] 16 Wire feeder

[0043] 18 Bending edge of the former

[0044] 20 Winding head

[0045] 22 Forming clamps

[0046] 24, 124 Forming jaws

[0047] 26, 126 forming jaws

[0048] 30 recess / gap

[0049] 100 Wave winding

[0050] K Collision point

Claims

1. A method for forming a wave winding by means of a flat former (10; 110) which is rotatable about its longitudinal axis, wherein: A plurality of parallel wires (14) are fed perpendicularly to the axis of rotation of the former (10; 110) by means of a wire feeder (16), wherein the wires (14) are alternately wound around the former (10; 110) by rotating the former stepwise and are formed into a wave winding (100) by means of a lateral shifting of the wires (14) already positioned on the former between the stepwise rotations, wherein the wire feeder (16) when winding the wires (14) The invention relates to a method for following the wire until it enters the area of ​​the shaper (10), characterized in that when the wire (14) is wound, the shaper (10) is first rotated less than 180 degrees, the winding head (20) that has just been partially formed is reshaped by the shaping jaws (24, 26; 124, 126) in an intermediate step, the wire feeder (16) is then withdrawn from the area of ​​the shaper (10), and finally the shaper (10) is rotated to 180 degrees for the final shaping of the winding head (20).

2. The method according to claim 1, characterized in that The forming jaws (24, 26; 124, 126) remain closed until the wire feeder (16) is removed.

3. The method according to claim 1 or 2, characterized in that: The forming jaws (24, 26; 124, 126) are brought into engagement with the wire (14) only for the duration of the forming process.

4. The method according to any one of the preceding claims, characterized in that The reshaping is performed by means of a single-sided recess (30) or two congruent recesses on both sides in the former (10) and correspondingly shaped forming jaws (124; 126), so that the wire (14) is initially bent more than 180 degrees relative to the wire position on the other side of the former (10).

5. The method according to any one of the preceding claims, characterized in that The former (10) is rotated to a certain angle before re-forming, at which angle the wire feeder (16) has just not yet contacted the former (10).

6. The method according to claim 5, characterized in that The former (10) is rotated about 175 degrees before re-forming.

7. A device for winding a wave winding (100) from a plurality of wires (14) fed in parallel by means of a wire feeder (16), the wires initially extending perpendicularly to the axis of rotation (12) of a flat sword-shaped former (10), the former being able to be rotated stepwise by means of a drive, and having means for reshaping the winding head (20), characterized in that The device for reshaping the winding head (20) comprises a pair of shaping jaws (24, 26; 124, 126) for reshaping the winding head (20), wherein the pair of shaping jaws (24, 26; 124, 126) are held on a movable device, and after the winding process is interrupted before the 180 degree rotation is achieved, the movable device brings the shaping jaws (24, 26; 124, 126) into the area of ​​the winding head (20) and reshapes the last produced winding head (20) there. The winding head is clamped against the former (10) and reshaped, and after the wire feeder (16) is retracted and the pair of forming jaws (24, 26; 124, 126) are released, the pair of forming jaws are removed from the rotation area of ​​the former (10) again before the drive device completes the rotation process of up to 180 degrees, wherein the movement of the drive device, the wire feeder (16) and the movable device is coordinated by means of a control device.

8. The device according to claim 7, characterized in that The control device interrupts the winding process before the wire feeder (16) comes into contact with the shaper (10), and the reshaping process of the winding head (20) produced finally takes place in a rotation angle position of the shaper (10) of about 175 degrees.

9. The device according to claim 7 or 8, characterized in that The forming jaws (24, 26; 124, 126) are formed on the forming clamp (22).

10. The device according to any one of claims 7 to 9, characterized in that The former (10) has a recess (30) in the region of the winding head (20) on one or both sides, which cooperates with correspondingly shaped forming jaws (124, 126) so that the wire guide can be bent over 180 degrees.

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