Method and device for producing a tape coil

Abstract

The invention relates to a method 200 for producing a tape winding 8, 9. The method 100 comprises the following steps: providing a tape 1, S1, winding the tape 1 onto a winding mandrel 5 to form winding layer groups 25, 26 of the tape winding 8, 9, S2, and cutting the winding layer groups 25, 26 twice to obtain winding base elements 18 and separate winding elements 19, S3. A ring core 22 and a device 100 for producing a tape winding 8, 9 are also provided.

Description

[0001] The invention relates to methods and devices for manufacturing a tape winding, a toroidal core, a choke and a transformer.

[0002] Chokes are inductive components and are coils used to limit currents in electrical conductors, to temporarily store energy in the form of their magnetic field, for impedance matching, or for filtering. Most chokes have a magnetic core because they then require significantly fewer turns for the same inductance compared to air-core chokes.

[0003] Transformers typically consist of two or more coils, usually wound from insulated copper wire, located on a common magnetic core. They are used, for example, for voltage conversion in power supply systems and technical devices. They are also required for signal transmission and protective isolation.

[0004] Magnetic cores consist of a soft magnetic material with the highest possible magnetic saturation flux density and high magnetic permeability. This allows the magnetic flux generated when current flows through the coil's electrical conductor to be focused and guided with minimal loss, thereby increasing the inductance. High permeability increases the magnetic field of an inductor by up to five orders of magnitude compared to an inductor with an air core, allowing the dimensions of an inductor with a magnetic core to be smaller than those of an air-core inductor.

[0005] To combat eddy current losses, the magnetic cores of transformers and electric motors are not solid, but laminated. These die-cut or cut electrical steel sheets are coated with a heat-resistant and insulating lacquer and stacked into blocks or rolled into rings, oriented parallel to the magnetic field lines. The magnetic flux is thus distributed across individual, separate fluxes within each sheet, resulting in only smaller eddy currents. The overall power loss from these eddy currents is therefore significantly lower than in a solid material. The sheets are typically less than 1 mm thick. The thinner the sheet, the lower the eddy current losses and, consequently, the higher the permissible operating frequency.

[0006] Laminated magnetic cores are primarily used in the low-frequency range of 16 to 400 Hz. Wound tape cores with tape thicknesses around 20 µm, however, can be used up to 100 kHz. For high-frequency applications, powder cores or ferrite cores are predominantly used for transformers, coils, and chokes.

[0007] One method for manufacturing transformer cores from electrical steel is by stacking cut sheets. Sections are produced from coils of varying widths and arranged into a rectangle or a rectangle with a central rib. Using different sheet widths results in an oval core cross-section. The sheets are stacked in such a way that after a certain number of sheets, there is a lateral overlap, which improves the magnetic flux. Due to the rectangular shape and the use of straight sheets, the magnetic flux of a three-phase transformer—that is, with sheet sections arranged in a rectangle with a central rib—consists of six connection points, namely four in each magnetic flux circuit, which negatively affects the permeability.

[0008] Alternatively, ribbon cores can be wound from a thin, soft magnetic strip with a thickness between (typically and depending on the alloy) 20 µm and 1 mm. The simplest and most cost-effective form to manufacture is a toroidal ribbon core. Except for the negligible transition between the strip layers, this creates an ideal, closed magnetic circuit with a uniform cross-section. The dynamic properties are largely determined by the alloy used and the strip thickness.

[0009] Ring cores are typically manufactured from a long strip, which usually first needs to be cut to the required width. They are therefore also called cut cores. The strip is wound into a core using a winding machine. After winding, a heat treatment is performed to adjust or specifically improve the magnetic properties of the core, depending on the alloy, at temperatures between approximately 200 °C and 600 °C. During the heat treatment, the material changes not only magnetically but also mechanically. Amorphous and nanocrystalline alloys are quite brittle after heat treatment and can therefore be easily damaged mechanically.

[0010] For example, WO 2023 / 218101 A1 describes a method for manufacturing a toroidal core with the following steps: providing a soft magnetic tape on at least two tape reels; unwinding the tape from two tape reels and winding the tape onto two spaced-apart mandrels to form a multi-layered first tape roll by rotating the mandrels around a first axis of rotation, inserting a separating element into the forming first tape rolls after several layers; reducing the distance between the mandrels until the first tape rolls touch each other; unwinding the tape from two tape reels and winding the tape into a multi-layered second tape roll that encircles the first tape rolls by rotating the mandrels around a common second axis of rotation, inserting a separating element into the forming second tape roll after several layers;Gradually cutting the tape reels into a plurality of tape sections; picking up at least one spool and placing the spool on the tape sections; shaping the free ends of the tape sections and joining the ends of the tape sections to form a closed ring.

[0011] The object of the present invention is to provide improved methods and devices for manufacturing a toroidal core. An improvement in the magnetic properties would be desirable. Furthermore, a simplification of the manufacturing process for transformers of the described type would be desirable.

[0012] This problem is solved by the subject matter of the independent claims. The dependent claims concern specific configurations.

[0013] A first aspect of the invention relates to a method for producing a tape winding, wherein the tape winding can, for example, be a toroidal core or can be processed into a toroidal core. The method comprises: providing a tape, winding the tape onto a winding mandrel to form winding layer groups of the tape winding, and cutting the winding layer groups twice, in particular exactly twice, to obtain winding base elements and separate winding elements.

[0014] In this context, a ring core is understood to be a multi-layered ring core, i.e., a magnetic circuit in a closed ring shape, for example in the form of a toroid or a rounded rectangle, which is made from a wound band or band winding.

[0015] In this context, a strip is understood to be a strip of material whose lateral dimensions, lying in one plane of extension of the strip, significantly exceed the thickness of the strip. Preferably, the lateral dimension in one direction of extension, the length of the strip, is significantly larger than in the other direction of extension, the width of the strip.

[0016] The tape preferably comprises or consists of a soft magnetic material. More preferably, the material thickness or thickness of the tape can be in the range of 0.02 mm to 1 mm, for example, between 0.1 mm and 1 mm. The material thickness or thickness of the tape can preferably be more than 0.18 mm. The tape can comprise or consist of a grain-oriented or non-grain-oriented material.

[0017] In this context, a "soft magnetic material" is understood to be a material that can be easily magnetized in a magnetic field. Preferably, a soft magnetic material has a coercive field strength of less than 1000 A / m, and more preferably less than 500 A / m. A typical soft magnetic material is, for example, electrical steel, such as that made of an iron-silicon alloy. The electrical steel can be a non-grain-oriented material, e.g., in the form of a so-called dynamo or motor lamination, or a grain-oriented material, e.g., in the form of a so-called transformer or core lamination.

[0018] The tape can be provided on one or more tape reels, e.g., two, from which it can be unwound. The tape reel(s) can be part of a tape feeder.

[0019] The winding mandrel can, for example, be designed to rotate about a first axis of rotation, so that the tape winding can be formed by rotating the mandrel around this axis. It is also possible to produce several tape windings simultaneously, e.g., two tape windings, for example, by unwinding the tape from two tape spools and winding it onto two mandrels spaced apart, each forming a multi-layered first tape winding, by rotating the mandrels around their respective first axes of rotation.

[0020] Preferably, the winding mandrel can have a substantially cuboid geometry, so that windings with a substantially rectangular basic shape can be obtained.

[0021] Preferably, for each winding mandrel, tapes of different widths can be provided on at least two tape spools, so that tapes of different widths can be used to produce the tape winding. In one embodiment, at least four tapes of different widths can be used to form a ring core with a cross-section that has at least eight steps.

[0022] For example, a tape winding can be produced from at least two tapes of different widths, with the width varying from the inside out. This allows for the production of an inner tape winding with an increasing width from the inside out and / or an outer tape winding with a decreasing width from the inside out. Thus, a tape winding with a definable cross-sectional geometry, in particular an oval or ovalized cross-sectional geometry, can be produced.

[0023] To produce the tape winding, several, preferably multi-layered, winding layer groups are created, i.e., a first winding layer group and at least one further winding layer group. Each winding layer group can have a predetermined number of winding layers, whereby the number of winding layers can differ between the winding layer groups or be the same. For example, each winding layer group can be formed with a different tape width. The thickness of a winding layer can, for example, be between 2 mm and 30 mm.

[0024] Each winding layer group is cut at least twice, resulting in a winding base element and a separate winding element. The winding base element can subsequently form, for example, the E-element of the ring core or part thereof, while the separate winding element can subsequently form the yoke of the ring core or part thereof.

[0025] The cutting of the first winding layer group and all further described cuts can preferably be made outside of corner areas of the winding, so that the cut surfaces are as small as possible and the interruption of the magnetic flux is minimal. The position of the cut can further preferably be chosen such that the legs of the E-element of the toroidal core, which can be formed from the winding base element, can accommodate a coil.

[0026] Cutting through the individual winding layer groups simplifies, or even makes possible in the first place – depending on the total winding thickness – the separation of the toroidal core, thus enabling, for example, the insertion of a coil. The proposed method is particularly suitable for toroidal cores with a winding thickness of more than 300 mm, because at this thickness, cutting through with a single cut after completion of the winding is either impossible or only possible to a very limited extent and with considerable effort.

[0027] Furthermore, this method allows for a clean separation, enabling the most precise possible form-fitting joining of the winding base elements and the separated winding elements. In contrast, cutting through a completely wound ring core is either impossible or only possible with considerable effort due to the band thickness and properties. Moreover, the resulting cut surfaces are of lower quality, making the joining of the winding base elements and the separate winding elements more difficult.

[0028] Depending on the design, a coating can be applied to the tape before it is wound up, e.g., between unwinding and winding the tape.

[0029] The coating can be applied, for example, as a so-called baked-on coating, i.e., a coating that is thermally activated after the tape winding has been produced. The coating serves to electrically insulate the individual winding layers and, optionally, to bond them together, e.g., by gluing, in order to protect the geometric shape of the tape winding from deformation and / or to facilitate handling of the tape winding.

[0030] According to further embodiments, the method can further comprise: producing two inner tape windings according to a method as described above, bringing the two inner tape windings together until they touch each other, winding the tape onto the inner tape windings to form winding layer groups of an outer tape winding, and cutting through the winding layer groups of the outer tape winding twice, in particular exactly twice, to obtain winding base elements and separate winding elements.

[0031] In other words, two inner tape windings can first be produced as described, which are then wrapped together to produce a multi-layered outer tape winding, with the winding process being analogous to the production of the inner tape windings.

[0032] For example, a tape can be supplied on at least two tape reels. The tape is then unwound from the two reels and, to create the inner windings, wound onto two spaced-apart mandrels, each forming a multi-layered first winding, by rotating the mandrels around a first axis of rotation. The distance between the mandrels is then reduced until the inner windings touch. Finally, the tape is unwound from the two reels and wound onto a single, multi-layered outer winding that encircles the inner windings, by rotating the mandrels around a common second axis of rotation.

[0033] The separation cuts can be made for the outer tape winding in the same way as for the inner tape winding. Once the last two separation cuts have been made, the production of the winding core is complete.

[0034] The described process enables the production of a two-part toroidal core with an E-shaped element and a yoke by cutting each coil twice. This means that the magnetic field flux is interrupted at only three points, namely twice in each magnetic flux circuit, resulting in improved permeability and magnetic flux. Furthermore, it eliminates the sharp corners that occur with the use of stacked laminations in state-of-the-art techniques such as step-lap cores. This reduces susceptibility to harmonics and lowers eddy currents, which cause higher energy consumption and a high reactive power component.

[0035] The proposed method also allows for the separate, independent production of the tape windings, e.g., the two inner tape windings and the outer tape winding. The winding base elements and the separate winding elements of the tape windings can then be assembled separately into two parts, e.g., the yoke and the E-element. This can be advantageous for the overall production process.

[0036] For winding the tape and cutting the winding layer groups, the following two variants are among those suitable.

[0037] In the first variant, the tape is wound onto the winding mandrel to form the first winding layer group of the tape winding. This first winding layer group is then cut at least twice to obtain a winding base element and a separate winding element. These two steps are then repeated, with each repetition forming and cutting another winding layer group twice.

[0038] The formation of further winding layer groups and their severance is repeated until the desired total winding thickness is reached.

[0039] Preferably, the separated winding element can remain on the respective winding base element before the next winding layer group is wound, so that the separate winding element is wrapped along with the subsequent winding layer groups.

[0040] In other words, the winding process can be briefly interrupted to cut the relevant group of winding layers, preferably while the tape remains taut. After the cutting step, winding continues as before, wrapping around the cut or section. Only after the total winding thickness is reached are the separated winding elements removed together.

[0041] This has the advantage that the winding process can proceed as smoothly as possible and the band remains taut at all times. Readjustments are unnecessary.

[0042] In a second variant, the tape is wound onto the winding mandrel, forming winding layer groups, until a predetermined total winding thickness of the tape roll is reached. The winding layer groups of the tape roll are then cut twice.

[0043] The cutting process can be carried out in stages; that is, the outermost winding layer group can be cut first, followed by each subsequent winding layer group, until the first, innermost, winding layer group is also cut. Before cutting the next winding layer group, the separated winding elements formed are removed from the winding base element of that group to allow access for further cutting of the next winding layer group.

[0044] A combination of the described variants is also possible, i.e., the first and second variants can be combined both when producing a single tape winding and when producing inner and outer tape windings.

[0045] For example, for the inner tape windings, the separation may only occur after the inner winding core is completed. For the outer tape winding, however, the winding process is interrupted after winding a group of winding layers, as in the first variant, and two separation cuts are made. The resulting separated winding elements of the outer tape winding remain attached to their respective winding base elements and are subsequently wound accordingly.

[0046] Depending on the specific design, the tape winding(s) can be thermally treated before the individual winding elements are removed from the corresponding winding base elements. Such thermal treatment can be used to bond winding layers, for example, by means of the applied coating, such as the applied baking varnish. This can improve permeability and ensure that the winding base core (E-core) formed from the winding base elements and the separate winding core formed from the individual winding elements are fixed to the holding frame elements located on the winding mandrel.

[0047] Depending on the design, the cutting can be carried out at a cutting angle of 90° to an expansion plane of the band.

[0048] In this case, the cutting length corresponds to the thickness of the strip. This has the advantage that the cutting length is as short as possible and, consequently, the cut surface is as small as possible. This minimizes disruption to the magnetic flux.

[0049] All winding layer groups can be cut in the same cutting plane. This can facilitate the subsequent joining of the winding base elements and the separated winding elements.

[0050] Alternatively, the winding layer groups can be cut in different cutting planes, i.e., offset. The number of cutting planes can correspond to the number of winding layer groups, or several winding layer groups can be cut in the same cutting plane. The offset arrangement of the cutting surfaces results in minimal disruption of the magnetic flux.

[0051] According to further design variations, the cutting can occur at a cutting angle other than 90°, for example, a cutting angle greater than 90° or less than 90°, such as a cutting angle of 45°, relative to an expansion plane of the band. For example, a sawtooth structure can be formed.

[0052] The resulting lateral overlap can further improve the magnetic flux.

[0053] Preferably, the two cuts can be made at opposite angles to 90°, i.e., the first cut angle can be, for example, +45° and the second cut angle -45°. Such an opposite-angle cut can simplify the joining process.

[0054] According to further design variations, the tape can be pressed against the winding mandrel during winding, e.g. by means of pressure rollers.

[0055] This allows the tension of the band to be adjusted, resulting in a uniformly wound toroidal core. Furthermore, even if one winding layer is cut, the subsequent winding layers can be wound particularly evenly because the overall winding is stabilized by the pressure exerted on the winding mandrel.

[0056] According to further embodiment variants, the method can include picking up at least one coil and placing the coil on the winding base elements, as well as optionally fixing the coil.

[0057] The winding base elements can then be joined to the separate winding elements in a form-fitting manner to form a closed ring.

[0058] In this way, a transformer or a choke can be advantageously designed.

[0059] According to further variations, the tape can be made of a non-amorphous material or consist of a non-amorphous material. In other words, the tape can be a non-amorphous tape.

[0060] For example, the tape can have a thickness of at least 0.18 mm. In particular, wide tapes, e.g., up to 500 mm or up to 600 mm wide, can be used. In other words, the proposed method enables the winding of wide tapes and the manufacture of transformers and chokes that cannot be produced with amorphous materials.

[0061] According to further embodiments, the process can involve inserting separating plates into the forming tape coil.

[0062] These separating plates advantageously allow for limiting the cutting depth when cutting through a winding layer group, thus preventing damage to the winding layer group below.

[0063] Depending on the tape thickness, however, the separating plates can be dispensed with, namely when the tape thickness is so large that deviations from a preset cutting depth do not lead to any damage or at most to negligible damage to the underlying winding layer.

[0064] According to further embodiments, the method can, preferably as a final process step, include the application of a tension band or tension structure enclosing the entire ring core.

[0065] According to further embodiments, the process can involve inserting separating plates into a forming coil of tape.

[0066] These separating plates are intended to prevent the underlying material layer from being cut during a separation cut, especially with very thin strip thicknesses of, for example, less than 0.15 mm. The separating plate can be made of various materials, as it can optionally be removed after the cut. It is irrelevant whether the cut is made directly into the separating plate or whether there is a cutout in the plate at the cutting point. The separating plate can advantageously be made of a permanent magnet, which allows for easy fixation and removal after the cut. A cutout should be provided for a permanent magnet version.

[0067] Another aspect of the invention relates to a ring core. The ring core has two inner windings with winding base elements and separate winding elements, and an outer winding with winding base elements and separate winding elements, which surrounds the two inner windings. The winding base elements and separate winding elements are joined to form a closed ring.

[0068] The proposed ring core can, for example, be manufactured using a process as described above. The description of the process therefore also applies analogously to the ring core. The advantages of the manufacturing process are correspondingly associated with the ring core.

[0069] Another aspect of the invention relates to a choke or a transformer with a toroidal core as described above. The advantages of the toroidal core are therefore correspondingly associated with the choke or the transformer.

[0070] Another aspect of the invention relates to a device for producing a tape reel. The device comprises a tape feed device with at least one tape spool for providing a tape, a winding device with a winding mandrel for winding the tape into a tape reel, and a cutting device for cutting through winding layer groups of the tape reel twice to obtain winding base elements and separate winding elements.

[0071] The proposed device can, for example, be suitable for carrying out the above-described method for producing a coiled tape. Therefore, the above explanations of this method also serve to describe the proposed device. The advantages of this method are correspondingly linked to the proposed device.

[0072] The cutting device can preferably be designed as a mechanical cutting device, e.g. in the form of a cutting disc or a saw band.

[0073] Optionally, the device for producing a tape winding may, for example, have one or more of the following features: one or more pressure rollers designed to press the tape against the winding mandrel during angling; a winding device with two rotating winding mandrels arranged at a distance from each other for winding the tape, wherein the winding mandrels can be driven either rotating about a first axis of rotation or rotating about a common second axis of rotation, and wherein the winding mandrels are movable perpendicular to the axes of rotation to adjust their distance; two tape feed devices, each with at least one tape reel for providing a tape; an insertion device with at least one manipulator for inserting separator discs into a forming tape reel; a tape tensioning device for maintaining a predetermined tape tension; a coating device for applying a coating to the tape; a reel feed device with a manipulator for picking up and placing reels on the winding base elements.and / or a locking device with a manipulator for positively interlocking the winding base elements with the separate winding elements to form a closed ring.

[0074] Optionally, one, several, or all tape feed units can include at least two tape reels to provide tape of different widths. Furthermore, optionally, one, several, or all tape feed units can each have a multi-reel magazine to which at least two tape reels can be interchangeably attached.

[0075] The locking device may include a manipulator for attaching a tension band or tensioning structure enclosing the entire ring core.

[0076] The invention is explained below by way of example with reference to the accompanying figures and preferred embodiments, wherein the features shown below can represent an aspect of the invention both individually and in various combinations with one another. The figures show: Figs. 1a to 1b show a schematic diagram of the tape winding process in a front view; Figs. 2a and 2b show a schematic diagram of the tape winding process in a top view; Fig. 3 shows a schematic diagram illustrating the production of a first winding layer group of an inner tape winding according to a first embodiment; Fig. 4 shows a schematic diagram illustrating the double cutting of the first winding layer group and the production of further winding layer groups; Fig. 5 shows a schematic diagram illustrating the production of an outer tape winding; Fig. 6 shows a schematic diagram illustrating the separation of winding base elements and separate winding elements; Fig. 7 shows a schematic diagram illustrating coil assembly; Fig. 8 shows a schematic diagram of an exemplary transformer; Figs. 9a to 9c show schematic diagrams of various cutting sections.Figures 10a to 10k show schematic diagrams illustrating the manufacture of a ring core according to a further embodiment; and Figure 11 shows a flowchart of an exemplary method for manufacturing a ring core.

[0077] The figures are not necessarily detailed or to scale and may be enlarged or reduced to provide a better overview. Therefore, the functional details disclosed here are not to be understood as limiting, but merely as an illustrative basis to guide those skilled in this field of technology in using the present invention in a variety of ways.

[0078] In this respect, directional terminology such as "top," "bottom," "front," "back," "anterior," "rear," etc., is used with reference to the orientation of the described figures. Since components of embodiments can be positioned in a number of different orientations, the directional terminology serves for illustration and is in no way restrictive.

[0079] Referring to the Fig. 1a bis 1d As well as 2a and 2b, an exemplary general winding method and an associated device 100 for producing a ring core 22 with two inner band windings 8 and one outer band winding 9 are described below. The special features of the proposed method 200 and the corresponding device 100 are then described with reference to the Fig. 3 bis Fig. 11 explained in more detail.

[0080] The representations of Fig. 1a bis 1d Figure 1 shows a device 100 for manufacturing a toroidal core 22 with two tape spools 3 for providing a thin soft magnetic tape 1 and with two rotatably driven winding mandrels 5 for winding the tape 1 into multilayer tape coils 8, 9, the distance between which is adjustable, and with two coating devices 10 with nozzles for applying a coating to the tape 1. The winding mandrels 5 can be driven separately about a first axis of rotation 6 or together about a second axis of rotation 7, wherein the first axes of rotation 6 and the second axis of rotation 7 are aligned parallel to each other. The winding mandrels 5 have a rectangular cross-section adapted to the transformer to be manufactured, with frame elements, e.g., an upper retaining frame element 14 and a lower retaining frame element 15, of a retaining frame already integrated into the winding mandrels 5 (see Figure 1). Fig. 3 ) may be inserted. Whether the bands 1 are used as single or multiple bands is irrelevant for the proposed method. It only affects the productivity of the proposed device 100.

[0081] The upper and lower retaining frame elements described above are elements that are located on the winding mandrel or can be arranged on the winding mandrel and can be used to fix the winding layers. For this purpose, the winding layers can be fixed to the retaining elements before the winding core is opened, i.e., before the separate winding elements are removed from the winding base elements. This means that after opening the winding core, only the base winding mandrel is removed, while the retaining frame elements remain on the wound strip, for example, to improve handling.

[0082] As in the Fig. 2a und 2b As shown in a top view, the tape feeder 23 has not just a single tape spool 3 for each winding mandrel 5, but a multi-spool magazine 4 to which four tape spools 3 with tape 1 of different widths can be interchangeably attached. This allows the first or inner tape windings 8 on the winding mandrels 5 to be formed from up to four tapes 1 of different widths, with the width increasing from the inside out. After a certain number of layers of a tape 1 of a specific width have been wound, the multi-spool magazine 4 is repositioned so that winding continues with a tape 1 of a greater width. Winding begins with the narrowest tape 1. When the desired thickness of this tape 1 is reached, the winding is interrupted, the tape 1 is cut, and the next wider tape 1 is coupled to the narrower tape 1, e.g., with double-sided adhesive tape, and then the winding process continues.

[0083] After the desired thickness of the second strip is reached, the third and fourth strips are wound analogously. However, for the last (widest) strip, winding only takes place up to half the desired thickness. The winding of the strip 1 onto the winding mandrels 5 by rotation around the respective first axis of rotation 6 with direction 17 is described in Fig. 1b and Fig. 2a depicted.

[0084] The winding process is then stopped and the winding mandrels 5 are moved towards each other in a plane perpendicular to the axes of rotation 6, 7 (see arrows in Fig. 1c ), until the inner band coils 8 touch each other (shown in Fig. 1c and Fig. 2b ). Now, the unwinding from both tape feed devices onto the two previously produced first tape winders 8 takes place simultaneously, by rotating the two winding mandrels 5 together around the second rotary axis 7 arranged between them, so that a second or outer tape winder 9 is created that encloses the two first tape winders 8 (shown in Fig. 1d and Fig. 2b ).

[0085] The bandwidth is reduced by one step each time the desired thickness is reached. This results in an overall ovalized core cross-sectional geometry.

[0086] If coating the strip 1 is desired, this can be applied continuously during the winding process using the coating device 10. In this case, however, a multi-layered strip 1 should not be used.

[0087] Fig. 3 shows a device 100 for producing a tape winding 8, 9. Analogous to the Fig. 1 and 2 As described, a soft magnetic strip 1, supplied in the form of a coil (not shown), is wound. In the exemplary embodiment, the strip 1 is made of a non-amorphous material with a strip thickness of at least 0.18 mm. Coming from the coil, the strip 1 is transported in the transport direction 2 to a coating device 10, where it is coated on one side with a baking varnish. This coating serves for electrical insulation and to bond the individual winding layers after thermal activation of the baking varnish. The thermal activation takes place after completion of the winding and cutting processes and before the winding core is opened.

[0088] The tape 1 is guided to the winding mandrel 5 with the upper retaining frame element 14 and the lower retaining frame element 15 via an optional deflection roller 24 and wound onto it by rotating the winding mandrel 5 about its first axis of rotation 6 in the direction of rotation 17. A plurality of elastically spring-loaded pressure rollers 16 are provided, which press the tape 1 against the winding mandrel during winding (see arrows associated with the pressure rollers in [reference]). Fig. 3 ). By wrapping several layers of wrapping material, a first group of wrapping layers 25 is formed.

[0089] After the formation of the first winding layer group 25 with a predetermined number of winding layers, the winding process is interrupted, i.e., the rotational movement of the winding mandrel 5 is stopped.

[0090] Now, using a cutting device, e.g., a cutting disc, two cuts 12 are made, dividing the first winding layer group 25 into a winding base element 18 and a separate winding element 19. The cuts are positioned such that a winding base element 18 with legs 20 (see Fig. 6 ) is obtained, which can accommodate a coil 13.

[0091] After the two separation cuts have been made, the separated winding element 19 remains attached to the winding base element 18. The winding process is carried out as described in Fig. 4 As shown, the process continues by setting the winding mandrel 5 into rotation again. This forms another winding layer group 26 with several winding layers, which is then also divided into a winding base element 18 and a separate winding element 19 by means of two separating cuts. As shown in Fig. 4 As shown, the separation cuts 12 can be slightly offset from each other. For further details of possible separation cuts 12, refer to the Fig. 9a bis 9c and the corresponding description is referenced.

[0092] The winding and double-separation steps are then repeated until the desired number of winding layer groups 25, 26 for the inner tape winding 8 is reached. A total of two inner tape windings 8 are produced according to the described method, e.g., using a device 100 as shown in Fig. 1 and Fig. 2 shown.

[0093] Then, as in Fig. 5 As shown, an outer tape winding 9 is produced. For this purpose, the two inner tape windings 8 are brought together until they touch each other. The pressure rollers 16 located in the contact area are removed beforehand. The tape is then wound onto the inner tape windings 8 to obtain a first winding layer group 25 of the outer tape winding 9. For further details, refer to the description of the Fig. 1c, 1d as well as 2b.

[0094] During the production of the outer tape winding 9, the winding process is also stopped after obtaining the first winding layer group 25 in order to cut the first winding layer group 25 twice. Subsequently, further winding layer groups 26 are wound and also each cut twice until the desired total winding thickness is reached and a bound double winding is obtained.

[0095] After completion of the winding process, all separate winding elements 19, i.e., the separate winding elements of the two inner band windings 8 and the separate winding elements of the outer band winding 9, are separated together from the corresponding winding base elements 18 by releasing the connection at the separation cuts. The winding base elements 18 remain attached to the upper retaining frame element 14 and form an E-shaped element that encompasses the three legs 20 of the ring band core 22. The separate winding elements 19 remain attached to the lower retaining frame element 15 and form the yoke 21 of the ring band core 22 (see Fig. 6 In other words, the core is opened to allow for the insertion of a coil, as explained in more detail below.

[0096] As in Fig. 7 As shown, coils 13 are then pushed onto the legs 20 of the winding base elements 18, or the coils 13 are positioned ready and the legs 20 of the winding base elements 18 are lowered into the coils 13.

[0097] The windings are then closed again by positively joining the winding base elements 18 with the corresponding separate winding elements 19, forming a closed ring and thus the toroidal core 22 as a closed transformer core with coils, i.e. a transformer 300 is formed (see Fig. 8 ). A closed choke core and a choke can be manufactured in an analogous manner.

[0098] To support the joining or closing process, a tension band can be placed around the fully wound transformer core, which may already have been fixed in the upper retaining frame 14.

[0099] In the Fig. 9a bis 9c Several exemplary separation cuts are shown, which can be used to separate winding base elements 18 and separate winding elements 19 from each other. The illustrated variants can be combined as desired to create the two separation cuts for each winding layer group 25, 26.

[0100] Fig. 9a Figure 1 shows an embodiment in which the cutting of each winding layer group 25, 26 takes place at a cutting angle α that deviates from 90° with respect to an extension plane 27 of the strip 1, namely at an angle of 45°. That is, the cutting plane 28 and the extension plane 27 enclose a cutting angle α of 45°. The cutting planes 28 are offset from each other, preferably at a constant distance, so that the Fig. 9a The sawtooth structure shown results.

[0101] Fig. 9b Figure 1 shows an embodiment in which the cutting of each winding layer group 25, 26 is carried out with a cutting angle α of 90° with respect to an extension plane 27 of the strip 1. That is, the cutting plane 28 and the extension plane 27 enclose a cutting angle α of 90°. The cutting planes 28 of the individual winding layer groups 25, 26 differ, so that the Fig. 9b The stage structure shown will be preserved.

[0102] Fig. 9c Figure 1 shows an embodiment in which the cutting of each winding layer group 25, 26 also takes place with a cutting angle α of 90° with respect to an extension plane 27 of the strip 1. That is, the cutting plane 28 and the extension plane 27 enclose a cutting angle α of 90°. The cutting planes 28 of the individual winding layer groups 25, 26 are identical, so that the Fig. 9b The continuous structure shown is maintained.

[0103] With reference to the Fig. 10a bis 10k An alternative method 200 for manufacturing a tape winding 8, 9 is explained below. This method 200 provides that the two inner tape windings 8 and the outer tape winding 9 are manufactured separately from each other.

[0104] To produce an inner tape winding 8, a first winding layer group 25 is wound. For the subsequent separation process, a separating insulation 11 is inserted in the area of ​​the later separated winding elements 19 during the winding of the tape 1 after completion of the first winding layer group 25. This separating insulation is intended to prevent the individual separated winding elements 19 from sticking together by preventing the adhesive effect of the previously applied coating. Subsequently, all further winding layer groups 26 are wound, with a separating insulation 11 being inserted after each winding layer group 26. After completion of this process, i.e., reaching the desired total winding thickness, the Fig. 10a The depicted tape winding 8 is obtained.

[0105] As in Fig. 10b As shown, two separation cuts 12 are then made, which separate the outer winding layer group 26 into a winding base element 18 and a separate winding element 19. The separate winding element 19 is then removed from the winding base element 18 ( Fig. 10c This process is repeated for all further winding layer elements 25, 26, as described in the Fig. 10d bis 10i is shown. After completion of this process, as shown in Fig. 10j shown, a plurality of winding base elements 18 and a plurality of separate winding elements 19 for an inner band winding 8 are obtained.

[0106] The outer tape winding 9 is produced in an analogous manner, as exemplified in Fig. 10k as shown. Furthermore, the production of the tape windings 8, 9 is carried out as described in the first embodiment.

[0107] The resulting winding base elements 18 and separate winding elements 19 of the band windings 8, 9 can then be assembled. Subsequently, as described above, Fig. 7 As described, coils 13 are arranged. Then the winding base elements 18 and separate winding elements 19 are positively connected to each other, as described below. Fig. 8 described.

[0108] A combination of the two described methods is also possible, i.e., the inner band windings 8 can, for example, be arranged as in the Fig. 10a bis 10j described as being manufactured, while the outer band winding 9 is as described for the Fig. 3 und 4 described as being manufactured.

[0109] Fig. 11 Figure 1 shows a flowchart of an exemplary process 200 for manufacturing a ring core 22. In a first process step S1, a soft magnetic strip 1 is provided. In process step S2, this strip 1 is wound onto a mandrel 5 to form a first winding layer group 25 of an inner strip winding 8. Subsequently, in process step S3, this first winding layer group 25 is cut twice. Process steps S2 and S3 are repeated until the desired number of winding layer groups 25, 26 of the strip winding 8 is reached.

[0110] Furthermore, process steps S1 to S3 are carried out twice to produce two inner tape windings 8. Preferably, both inner tape windings 8 can be produced simultaneously.

[0111] The process 200 then continues with process step S4. In process step S4, the two inner tape windings 8 are brought together until they touch each other. In process step S5, the tape 1 is wound onto the two inner tape windings 8 to obtain a first winding layer group 25 of an outer tape winding 9. In process step S6, the first winding layer group 25 of the outer tape winding 9 is separated twice. Process steps S5 and S6 are repeated until the desired number of winding layer groups 25, 26 of the tape winding 8 is reached.

[0112] Preferably, the separated winding elements 19 remain attached to their associated winding base elements 18 until the total winding thickness is reached, and are only then separated from each other to open the tape winding 8, 9. Alternatively, the separated winding elements 19 can be removed directly from their associated winding base elements 18 after being cut twice.

[0113] In process step S7, one or more coils 13 are picked up and placed on the winding base elements 18. In process step S8, the winding base elements 18 are then joined with the separate winding elements 19 to form a closed ring in a form-fitting manner.

[0114] Further exemplary embodiments of the invention can be described as follows: The invention can be characterized in that two identical inner winding cores and an outer winding core, which is larger and geometrically encloses the two inner winding cores, are produced. To enable an oval core shape, the winding of the inner cores can begin with a narrow strip of sheet metal. The width of the sheet metal strip can be varied in equal or different increments up to the maximum desired width. During the production of the winding, the sheet metal strip can be coated with an insulating adhesive or insulating varnish. This type of coating can also be applied beforehand with a so-called baking varnish, which is thermally activated after the winding has been produced.The invention can further be characterized in that double insulating papers or other materials are inserted at certain intervals, which ensure a partial interruption of the bond.

[0115] When producing the outer winding, the winding process can begin with the maximum sheet width and then proceed in stages down to the minimum sheet width. Partial separating insulation can also be incorporated during winding to interrupt the bond. The resulting sheet windings are then cut in stages by two lateral cuts. These cuts can be made at an angle other than 90° (preferably 45°) and only to a defined depth, matching the depth at which the separating insulation was inserted. Multiple cuts on both sides create a sawtooth pattern at the cut point. The separated winding sections are then rejoined separately, mirroring their previous layer.

[0116] The sections of the inner windings are placed into the separated lower part of the outer winding. The resulting beam (yoke) forms the closure of the transformer core. The upper winding sections are also joined so that the outer winding section encloses the inner winding sections, forming an "E" shape. Transformer coils are slid over the legs of the "E," and the "E" is closed with the lower yoke. The individual elements are fixed in place using a holding frame, analogous to prior art. Due to the stepwise separation of the individual windings at an angle (greater or less than 90° – preferably 45°), a sawtooth structure is achieved, similar to the overlap in conventional transformer core manufacturing, which allows for improved magnetic flux.

[0117] Furthermore, the invention is characterized in that, through this structure, the magnetic flux is interrupted only at three points (twice each in the magnetic flux circuit), which also improves the permeability or the magnetic flux.

[0118] An extended winding and separating principle can provide for: Winding of a defined thickness, e.g., approx. 5-30 mm. Clamping of the material strip by pressing over rollers. Stop of rotation. One-sided cut, keeping the material strip taut. Winding over the cut. Stop of rotation. Cut the opposite cut, keeping the material strip taut. Winding over the second cut. Winding of a defined thickness. Repeat the cutting process. Winding of two inner core rings, including cuts. Bringing the two inner winds together. Continue winding the outer wind in the same manner. Bonding of the strip layers during the process. Fixing the double U-angle over the upper / lower support frame. Separation of the lower winding elements, including the lower support frame. Attaching the spools. Joining the lower support frame. Bezugszeichenliste

[0119] 1 Tape 2 Transport direction 3 Tape reel 4 Multi-spool magazine 5 Winding mandrel 6 First axis of rotation 7 Second axis of rotation 8 Inner tape winding 9 Outer tape winding 10 Coating device 11 Separation insulation 12 Separation cuts 13 Reel 14 Upper retaining frame element 15 Lower retaining frame element 16 Pressure roller 17 Direction of rotation 18 Winding base element 19 Separated winding element 20 Leg 21 Yoke 22 Ring core 23 Tape feed device 24 Deflection roller 25 First winding layer group 26 Further winding layer group 27 Expansion plane 28 Cutting plane 100Device 200Process 300Transformer αCutting angle S1 Providing a tape S2 Winding the tape onto a winding mandrel to form the first winding layer group of an inner tape winder S3 Cutting the first winding layer group of the inner tape winder twice to obtain a winding base element and a separate winding element S4 Joining the two inner tape winders until they touch S5 Winding the tape onto the inner tape winders to form the first winding layer group of an outer tape winder S6 Cutting the first winding layer group of the outer tape winder twice to obtain a winding base element and a separate winding element S7 Picking up a spool and placing the spool onto the winding base elements S8 Form-fitting joining of the winding base elements with the separate winding elements to form a closed ring

Claims

1. Method (200) for producing a tape winding (8, 9) comprising the method (100): - providing a tape (1) (S1), - winding the tape (1) onto a winding mandrel (5) forming winding layer groups (25, 26) of the tape winding (8, 9) (S2, S5), and - cutting the winding layer groups (25, 26) twice to obtain winding base elements (18) and separate winding elements (19) (S3, S6).

2. Method (200) according to claim 1, comprising: - producing two inner tape windings (8) according to a method (100) according to claim 1, - bringing the two inner tape windings (8) together until they touch each other (S4), - winding the tape (1) onto the inner tape windings (8) to form winding layer groups (25, 26) of an outer tape winding (9) (S5), and - cutting the winding layer groups (25, 26) of the outer tape winding (9) twice to obtain winding base elements (18) and separate winding elements (19) (S6).

3. Method (200) according to claim 1 or 2, wherein (i) the tape (1) is wound onto the winding mandrel (5) to form a first winding layer group (25) of the tape winding (8, 9) (S2), (ii) the first winding layer group (25) is cut twice to obtain a winding base element (18) and a separate winding element (19) (S3), and (iii) steps (i) and (ii) are repeated by forming and cutting twice a further winding layer group (26) until a predetermined total winding thickness of the tape winding (8, 9) is achieved.

4. Method (200) according to claim 3, wherein the separated winding element (19) remains attached to the respective winding base element (18) during the repetition of step (i) and is wrapped along with the further winding layer groups (26) during the formation of the.

5. Method (200) according to claim 1 or 2, wherein the tape (1) is wound onto the winding mandrel (5) forming the winding layer groups (25, 26) until a predetermined total winding thickness of the tape winding (8, 9) is reached, and subsequently the winding layer groups (25, 26) of the tape winding (8, 9) are cut twice.

6. Method (200) according to one of the preceding claims, wherein the cutting is carried out at a cutting angle α of 90° to an extension plane (27) of the strip (1).

7. Method (200) according to claim 6, wherein all winding layer groups (25, 26) of a tape winding (8, 9) are cut in the same cutting plane (28) or in different cutting planes (28).

8. Method (200) according to one of the preceding claims, wherein the cutting is carried out at a cutting angle α deviating from 90°, for example a cutting angle α of 45°, to an extension plane (27) of the strip (1).

9. Method (200) according to one of the preceding claims, wherein the tape (1) is pressed against the winding mandrel (5) during winding.

10. Method (200) according to one of the preceding claims, comprising - receiving at least one coil (13) and placing the coil (13) on the winding base elements (18) (S7).

11. Method (200) according to claim 10, comprising - positive-locking joining of the winding base elements (18) with the separate winding elements (19) to form a closed ring (S8).

12. Method (200) according to one of the preceding claims, wherein the band (1) comprises a non-amorphous material.

13. Ring core (22) comprising: - two inner band windings (8) with winding base elements (18) and separate winding elements (19), and - an outer band winding (9) with winding base elements (18) and separate winding elements (19) which surrounds the two inner band windings (8), wherein the winding base elements (18) and separate winding elements (19) are joined in a form-fitting manner to form a closed ring.

14. Choke or transformer (300) with a toroidal core (22) according to claim 13.

15. Device (100) for producing a tape winding (8, 9), comprising - a tape feed device (23) with at least one tape spool (3) for providing a tape (1), - a winding device with a winding mandrel (5), designed for winding the tape (1) into a tape winding (8, 9), and - a cutting device, designed for cutting through winding layer groups (25, 26) of the tape winding (8, 9) twice to obtain winding base elements (18) and separate winding elements (19).

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