EP3803923A1 - Inductive component and method for producing same - Google Patents

Abstract

The invention relates to an inductive component, which has an annular core having a core cross section and made of a soft-magnetic material and a coil surrounding the core, the coil being composed of two electrically conductive sections. The sections each have a basic U shape with two limbs, of which the first limb is longer than the second limb and the first limb is curved and towards the end of same projects away from a plane defined by the basic U shape. The sections are pushed onto the core next to one another so that the basic U shape of each section surrounds the core cross section on three sides. The first limb of a section is mechanically and electrically connected to the second limb of the other section. A method for producing a component of this kind is also described.

Description

 INDUCTIVE COMPONENT AND METHOD FOR THE PRODUCTION THEREOF

description

The invention relates to an inductive component and a method for its production.

In the manufacture of inductive components having annular cores and thick-wire windings, the mechanical loading of the toroidal cores is high due to the winding tension occurring during winding. To achieve a tight fit of the wires, the wire must be pulled taut as it passes through the ring core. The resulting forces are essentially absorbed by the edges of the ring core. The ring core itself or a housing enclosing it must therefore have a corresponding strength in order to avoid damage to the toroidal core or other impairments. Since in many applications toroidal cores have a small volume and are intended to be highly permeable, the nuclear material is to be protected from the forces acting thereon by the magnetostriction. Accordingly, the housing or other enclosure should be self-supporting, and absorb the forces occurring in the winding without deforming and without the forces te to pass on the toroidal core.

However, it is problematic to wind Ringkeme in a conventional housing with thicker wires, for example, for use with higher currents. With conventional plastic housings for toroidal cores with wall thicknesses of 1-2 mm, the possibilities for winding with customary winding techniques end with wire diameters of 2-3 mm copper wire. For example, to permit the use of thicker wires, much stronger plastic housings may be used, or multi-stranded strands, such as high-frequency strands, may be used for winding. Stronger housings entail higher tensile forces, but usually increase the costs and the construction volume. Multicore strands improve the distribution of tensile force, but have other disadvantages such as a poorer high-frequency behavior due to increased capacities between the windings, higher wire costs and higher costs for the connection technology.

It is therefore desirable to provide inductive components with sensitive magnetic material that is compatible with the existing plastic housings and their strength, as well as a manufacturing method for such toroidal cores.

An inductive component is provided, which has a core having a core cross-section of soft magnetic material in ring form and a winding surrounding the core, which is composed of two electrically conductive sections. The sections each have a U-basic shape with two legs, of which the first leg is longer than the second leg and the first leg is bent and is towards its end by a plane defined by the U-basic shape plane away. The sections are mounted side by side on the core, so that the U-basic shape of each section surrounds the core cross-section on three sides. The first leg of a section is mechanically and electrically connected to the second leg of the other section.

In addition, a method for producing an inductive component is provided, in which on a Kemquerschnitt having Kem soft magnetic material in ring form two electrically conductive sections forming a winding adjacent to each other are placed on the core, so that the U-basic shape of each section to the core cross-section The sections each have a U-shape with two legs, of which the first leg is longer than the second leg and the first leg is bent and is towards its end by a plane defined by the U-basic shape plane away. The first leg of a section is mechanically and electrically connected to the second leg of the other section ver. The invention will be explained in more detail with reference to the embodiments illustrated in the figures of the drawing, wherein similar or identical elements are provided with the same reference numerals.

FIG. 1 shows, in a three-dimensional view, an exemplary section for use with a winding composed of two or more such sections.

FIG. 2 shows a plan view of the section shown in FIG.

FIG. 3 shows a plan view of the section shown in FIG. 1 when it is mounted on a ring core.

FIG. 4 shows, in a three-dimensional view, the section shown in FIG. 1 and a further section, when they are plugged onto a ring core and connected to one another.

FIG. 5 shows a three-dimensional view of an exemplary common-mode suppression choke with two windings composed of sections on a toroidal core.

Figure 6 shows a three-dimensional view of an alternative embodiment of the portion shown in Figure 3 on a toroidal core to achieve a reduced Windungsab stood.

Figure 7 shows in three-dimensional view the exemplary embodiment of the ends of sections before joining.

Figure 8 shows in three-dimensional view an alternative embodiment of the ends of sections before joining.

FIG. 9 shows a three-dimensional view of the ends of parts shown in FIG. 7 after joining. FIG. 10 shows, in a three-dimensional view, a further alternative embodiment of the ends of sections before the connection.

FIG. 11 shows in an impedance-frequency diagram the comparison of measurements of a common-wire suppression choke constructed of heavy-wire and a common-mode suppression choke constructed with the sections described herein.

It is envisaged to sammensetzen one or more windings of pre-bent conductor pieces, which are on or about an annular, soft magnetic core, hereinafter generally referred to briefly as a toroidal core or only core plugged, and then with a suitable connection technology together to form a winding electrically and mechanically get connected. These conductor pieces can be formed, for example, by basically U-shaped or U-shaped brackets, the type of conductor pieces and the manner of use depending in detail on the spatial structure and the number of joints. For example, the Ver binding technique is easy to implement and inexpensive, if only the smallest possible number of joints is provided and the joints are located on the outer circumference of the ring core. If you go from the smallest possible number of connec tion sites per turn, so exactly one connection point per turn, this can be achieved, for example, by a U-bracket shape and a bend after Aufste bridges. However, this bending step is usually carried out over the edge of the toroidal core, which in turn is connected to an impermissible force on the toroidal core. To prevent this comes a specially shaped conductor bracket is used, which is placed on the toroidal core and possibly by a largely for the toroidal force-strong rotation in the position for one turn. The ring core has, for example, amorphous or nanocrystalline material and, for example, the shape of a band, or is made entirely of it. For example, the tape may have a permeability between 200 and 150,000 inclusive. Economically significant is the possibility of using as few differently shaped wire hangers, that is, the number of different ironing shapes can be kept low. In addition, however, the connection technology is important. A winding alone is no longer reliable even with a single insufficient connection point up to a failure of the entire component. Each connection point is a combination of mechanical function, that is, stable positioning of the conductors, as well as electrical function, that is, setting Her and maintaining a permanently low-resistance electrical contact. In this case, an electrical connection point is sought in which the mechanical and electrical functions can be set largely independently or separately from one another. This is achieved, for example, by correspondingly formed ends of adjacent brackets are inserted into each other, so that a certain me chanical connection is already present without a final electrical contact, for example, by soldering or welding. For example, N can be plugged into one another, each of which forms a turn to each other plugged together a continuous winding with N turns.

Figure 1 shows a three-dimensional view of an example of such a single Bü gel 100 in approximate U-shape, the two statements 101 and 102 at the ends of two he legs 103 and 104 of the U-shape. For the sake of simplicity, no specific embodiments of one or both terminations 101 and 102 are shown. The U-shape of the bracket can be square or round or have any other configuration. Shown is a more angular shape with rounded corners. The leg 104 of the U-shaped bracket is longer than the other leg 103 and is approximately at the height of the conclusion 101, so approximately in a central region of the leg 104, bent away from the sem such that two certain angle a , ß form opposite to a surface defined by the U-shape. For example, one or both angles α, β may be at or about 90 degrees (± 45 degrees), such as between 80 degrees and 100 degrees inclusive. Figure 2 shows the bracket 100 in plan view. As can be seen from this, the two legs 103 and 104 have a distance a from each other. The distance a and thus the opening of the U-shape is dimensioned so that the bracket 100 can be inserted with its opening via a toroidal core with a width b.

In Figure 3, the bracket 100 is shown when it has been inserted over a ring core 300 with the width b. The length of the legs 103 and 104 depends, optionally together with other aspects, on the height (not shown in FIG. 3, but shown in FIG. 4 as height h) of the ring core 300.

FIG. 4 shows, in a three-dimensional representation, the case in which the bracket 100 and another identical bracket 100 'are attached to the ring core 300 and connected to one another. In each case a degree 101 of the bracket 100 and 100 'is executed at ge showed embodiment in the form of a round rod, while the other end 102 of the bracket 100 and 100' pressed flat and provided in the resulting surface with a (through) opening 400 which is complementary in terms of shaping and dimensions to the round bar of the closure 101, that is, corresponds to or fits into one another. An end 101 of the yoke 100, after being placed on the ring core 300, is rotated (with rotational elastic or nonelastic deformation) of the end portion of the leg 104 around the other portion of the leg 104 in the region of its central bend and by insertion of the termination 101 of the bracket 100 in the opening 400 of the also plugged onto the toroidal core 300 bracket 101 'with this verbun the.

The attachment can be done so that the first end portion of the leg 104 is fully inserted into the inner opening of the ring core 300 in the direction of the height h of the ring core 300, wherein the leg connecting portion of the bracket 100 extends in the radial direction of the ring core 300. The bracket is then tilted about the longitudinal axis of this section and aligned obliquely to the width b of the ring core 300. By adding more brackets and connecting the bracket - as explained above in connexion with Figure 4 - results in a gleichgeformte chain a plurality of interconnected bracket that form one or more windings. FIG. 5 shows an example of a current-compensated choke, that is to say a common-mode suppression choke

500 (or other inductor such as a transformer, choke, etc.) with two windings constructed (identical) as described above

501 and 502 on a ring core 503. Optionally, special Endbügel 504 and 505, each of which is used as the first or last bracket of a winding use and each having a prolonged (and possibly specially trained) completion circuit 506, whereby a simpler electrical contact is made possible , For example, the elongated round rod shaped terminations 506 can be easily inserted into holes in a printed circuit board and soldered, welded or clamped there with printed conductors of the printed circuit board. All connections of the individual brackets with each other are on the outside of the toroidal core and thus easily accessible during manufacture, inspection and repair of the device. The common mode suppression choke 500 may also have more than two windings, which are then arranged instead of two in four sectors of the toroidal core. The toroidal core encloses an inner circumference and the portions in the inner circumference may have a shape corresponding to circle segments, for example to allow for a tighter winding.

According to another embodiment shown in Ligur 6, the opening of the U-Lorm of the bracket, so the clear distance a whose both legs 103 and 104, also be selected to be larger than the later distance between the turns in modification of the embodiment shown in Ligur 3. For this purpose, after attaching the bracket 100 on the ring core 300, for example, the end portion of the longer's Article 104 are rotationally bent from a position X to a position Y, so that a distance c compared to the distance a between the turns is created, whereby the Sector of a turn (or the slope of the winding) is smaller. Now, although a (non-elastic) bending of the bracket is required, but this takes place in a rotational movement of the wire laterally of the ring core (for Example in the Innenöff ung the ring core), without significant forces acting on the toroidal core.

In all the embodiments described above and in all other conceivable embodiments, the electrical connection of the ironing ends, for example the ironing 101 and 101 'shown in Figure 4 by a suitable method such as resistance welding, laser welding, soldering, brazing, pressing, pressing , electrically conductive bonding or various combinations produced or existing contact (such as by prior press-fitting) can be improved. The joints between the temples are easy to set forth by the exposed, easily accessible position on the outer circumference of the core, but also easy to monitor individually by means of visual inspection and measurement of electrical properties.

FIG. 7 shows in detail the connection technique that can be used, for example, in the arrangement shown in FIG. 4, before joining, that is to say prior to nesting. The conclusion 101 of the bracket 100 (not completely shown in FIG. 7) is again in the form of a round bar, while the respective other end 102 of the bracket 100 '(not completely shown in FIG. 7) has been pressed flat. In the resulting surface, in turn, the (through) opening 400 has been introduced, which is complementary in terms of shape and dimensions to the round rod of the fin 101. The conclusion 101 of the bracket 100 is then perpendicular to the flattening of the fin 101 'in its opening 400 on and performed (where appropriate, pressed). In the assembled state (as shown in FIG. 4), an end section of the rounded-off end 101 projects through the opening 400 of the shallow end 102, forming a thermal depression, since this section is not current-flowed and thus is not heated by the current itself. whereby it can conduct heat from adjacent current-carrying sections from. Thus, the junction is (indirectly) cooled and will always have a lower temperature than other sections of the respective bracket or the winding. FIG. 8 shows a further embodiment in which the round-bar-shaped termination 101 has a recess or taper 800, which then forms a positive connection in the opening 400 by compression, so that the bars can be mechanically fixed to one another and thus possibly for one following (further) connection process such as welding or soldering no longer need to be held. FIG. 9 shows the two terminations 101 and 102 shown separately in FIG. 8 after being plugged together. By exerting pressure F on the sides of the end 102, compression and then non-elastic bending takes place. Such an approach also allows an alternative connection technique by soldering. If all the brackets are mechanical in the manner shown, but are also (sufficiently) electrically connected by the compression, a suitable, high electric current can be passed through the entire winding, which heats the yokes by means of Joule heat. Once the soldering temperature has been reached, the soldering can be carried out by supplying solder to the contact points. If the solder was applied as a paste on all contact points, a simultaneous soldering of all con tacts with a current pulse of certain duration is possible.

Ligur 10 shows an embodiment in which instead of the Vertie tion or taper 800 shown in Ligur 8 a survey or thickening 1000 is formed on the conclusion 101. A pressing is carried out already during the mating of the circuits 101 and 102. The then applicable connection technology largely corresponds to that described above.

Comparative measurements were carried out on different types of common-mode suppression chokes, the results of which can be seen from Ligur 11. On the one hand, two types of chokes were measured with the above-described "Bügeltechnolo gie" and other comparable, conventional two types of chokes in "heavy wire technology" with triple parallel strands. Thus, in the ironing technology, the associated impedance curve over the Lrequenz a Eigenreso nance (impedance drop) at higher frequencies than that of the conventional Strong-wire technology occurring impedance curve over the frequency. An attenuation of a common-mode noise signal is possible with the "heavy-wire technology" up to, for example, 8-100 MHz, but with the "ironing technology", for example, up to 15-20 MHz.

Due to the increasingly high load currents in filter applications, there is a compulsion to windings with thicker wires, so that the inductive component does not overheat. Above 3mm wire diameter, the hand wrapping of the cores in such applications can not be realized as usual by means of a crochet hook, since the winding forces are too high for the person winding and with increasing number of turns, the copper additionally hardens. Furthermore, the plastic trough can no longer absorb the mechanical forces and the core is in danger of being deformed. The previous solution was to provide the windings with several parallel wires (English strands). However, the winding capacitances (Cw) increase drastically and the natural resonance shifts to lower frequencies. An attenuation above a few MHz is therefore no longer possible. In addition, the parallel strands are associated with high production costs (high stripping time) and a somewhat larger installation space. The technology presented herein provides for a division of the winding into sections, such as stirrups, which can be pushed (or pushed) onto the core and, for example, connected together by means of automatic brazing.

It can thus be applied with the above-described technology windings of solid wire with a larger diameter on a toroidal core, with the Be particularities of toroidal cores such as those made of highly permeable material, which are generally sensitive to mechanical influences accordingly, can be taken into account. Furthermore, the technology allows the use of existing cores existing with existing plastic housings for wire thicknesses, which were previously not possible due to the burden of winding by the pressure on the toroidal core. For the core, this special type of "winding" is virtually stress- and energy-efficient. and theoretically limited only by the inner diameter of the core and the number of bracket segments used.

Claims

Claims: 1. Inductive component with:  a core having a core cross-section made of soft magnetic material in ring form and  a winding surrounding the core, which is composed of two electrically conductive parts, wherein  the sections each have a U-basic shape with two legs, of which the first leg is longer than the second leg and the first leg is bent and is at its end away from a plane defined by the U-basic shape plane away;  the sections are mounted side by side on the core, so that the U-basic shape of each section surrounds the Kemquerschnitt on three sides, and  the first leg of a section is mechanically and electrically connected to the second leg of the other section. 2. Inductive component according to claim 1, wherein the first leg is at its end at two angles to the plane defined by the U-basic shape plane away, wherein at least one of the two angles between 80 degrees and 100 degrees. 3. Inductive component according to claim 2, wherein at least one of the two win angle is 90 degrees. 4. Inductive component according to one of claims 1 to 3, wherein the first leg of one of the sections and the second leg of the other of the sections are formed at their ends plugged into each other. 5. The inductive component according to claim 4, wherein the first leg of one of the sections is flattened at its end and has an opening of a certain shape. and the second leg of the other of the sections has at its end a shape complementary to the particular shape of the opening so that the second leg of the other of the sections is inserted into the opening of the first leg of the one of the sections. 6. Inductive component according to claim 5, wherein the second leg of the other of the sections is inserted into the opening of the first leg of one of the sections rechtwink lig to the flattening. 7. Inductive component according to claim 5 or 6, wherein the second leg of the other of the sections is inserted into the opening of the first leg of one of the sections at right angles to the flattening. 8. Inductive component according to one of claims 5 to 7, wherein  the opening at the first leg of the one of the sections is round and has a Öffhungsdurchmesser and  the end of the second leg of the other of the sections is round-bar-shaped with a bar diameter that is slightly smaller than the opening diameter. 9. Inductive component according to claim 8, wherein the end of the second leg of the other of the sections is positively pressed into the opening at the first leg of the nen one of the sections. 10. Inductive component according to one of claims 1 to 9, wherein the first's angle of one of the sections and the second leg of the other of the sections connected at their ends by at least one compound from the group soft soldering, brazing, welding and electrically conductive bonding are. 11. Inductive component according to one of claims 1 to 10, wherein the sections are made of round wire. 12. The inductive component according to claim 11, wherein the round wire has a diameter ranging between 2mm and 50mm inclusive. 13. Inductive component according to claim 11 or 12, wherein the round wire comprises copper or consists of copper. 14. Inductive component according to one of claims 1 to 13, in which the sections are at least partially covered with an electrically insulating layer. 15. The inductive component according to claim 1 to 14, wherein the core has amorphous or nanocrystalline band, wherein the band has a permeability of 200-150000. 16. Inductive component according to claim 1 to 15, wherein the core is enclosed by an electrically insulating housing. 17. Inductive component according to claim 16, wherein the housing comprises plastic or consists of plastic. 18. Inductive component according to one of claims 1 to 17, comprising at least one additional, composed of sections winding or at least one addi ches section of a winding or both. 19. An inductive component according to claim 18, wherein the first and last part of a winding has a formed for external contacting first or second leg. 20. A method for producing an inductive component, in which having on a core cross-section core of soft magnetic material in ring form two electrically conductive sections forming a winding side by side be placed on the core, so that the U-basic shape of each section of the core cross-section surrounds on three sides, wherein the sections each have a U-basic shape with two legs, of which the first leg is longer than the second leg and the first leg is bent and stands at its end away from a plane defined by the U-basic form, and  the first leg of a section is mechanically and electrically connected to the second leg of the other section. 21. Method according to claim 20, wherein the first limb is bent towards its end at two angles with respect to the plane defined by the U-basic form, at least one of the two angles being between 80 degrees and 100 degrees. 22. The method of claim 21, wherein at least one of the two angles is 90 degrees. 23. The method according to any one of claims 20 to 22, wherein the first leg of one of the sections and the second leg of the other of the sections are formed at one end plugged into each other. 24. The method of claim 23, wherein  the first leg of the one of the sections is flattened at its end and an opening of a certain shape is introduced into the flattening and  the second leg of the other of the sections has at its end a shape complementary to the particular shape of the opening and the second leg of the other of the sections is inserted into the opening of the first leg of the one of the sections. 25. The method of claim 24, wherein the second leg of the other of the parts is inserted into the opening of the first leg of one of the sections at right angles to flattening. 26. The method of claim 24 or 25, wherein  the opening at the first leg of the one of the sections is round and has a Öffhungsdurchmesser and  the end of the second leg of the other of the sections is round-bar-shaped with a bar diameter that is slightly smaller than the opening diameter. 27. The method of claim 26, wherein the end of the second leg of the other of the sections is positively pressed into the opening at the first leg of the one of the partial pieces. 28. The method according to any one of claims 20 to 27, wherein the first leg of one of the sections and the second leg of the other of the sections at their ends by at least one compound from the group of soldering, brazing, Ver welding and electrically conductive bonding are joined together , 29. The method according to any one of claims 20 to 28, wherein the sections are made of round wire. 30. The method according to any one of claims 20 to 29, wherein the portions are at least partially covered with an electrically insulating layer or are. 31. The method of any one of claims 20 to 30, wherein the two sections of the first leg of both sections are bent at each of their bending after fitting to the core in the region of the existing curvature against each other.