Coil and method for producing the coil

Abstract

A coil (1) comprising a tube (2) with a tube wall (6) made of an electrically conductive material, wherein the tube (2) has an inductive section (7) in which a gap (4) is arranged in the tube wall (6) forming the tube wall (6) into a helix in the inductive section (7), and wherein the tube (2) has two contact sections (8) comprising a connection area (10) and at least one terminal area (11), wherein the connection area (10) has the same contour as an adjacent section of the helix, and wherein the terminal area (11) forms an electrical connection of the coil (1), and wherein the connection area (10) electrically connects the terminal area (11) to the inductive section (7). Further aspects relate to a module comprising several coils (1), a method for manufacturing a coil (1), and a method for manufacturing a module.

Description

[0001] The invention relates to a coil comprising a tube made of conductive material, and a method for manufacturing the coil.

[0002] The publication DE 10 2019 103895 A1 describes a coil and a method for its manufacture.

[0003] Document US 5 428 337 A describes a conductive winding.

[0004] The publication JP H11 97270 A describes a flat coil and a method for its manufacture.

[0005] In the course of miniaturizing electrical circuits, it is of great interest to provide small inductive components that exhibit low power loss, high current carrying capacity and reliable durability.

[0006] Especially with wire coils, a weak point can be the connection between the wire and a contact element required for external contact. These connections, usually made with welds or solder joints, can exhibit at least a slightly increased resistance due to the alloy used, which contains copper, tin, or nickel, or due to contamination with oxygen. If the contact is poorly executed, the resistance can be significantly increased. This can result in high contact resistance, leading to high power loss. Consequently, increased thermal stress can also occur at this point, potentially causing coil failure in a minor scenario or, in a more serious case, a fire. can.

[0007] Especially with small coils, the design of the contacts and the lead wire of the coils has a significant impact on the electrical properties of the coil. out of. The large ratio of the dimensions of the leads to the dimensions of the coil has a considerable impact on the properties of the coil as an electronic component. out of.

[0008] The object of the present invention is it, to provide a manufacturing process for a module that has at least two coils.

[0009] The present problem is solved by the method according to claim 1.

[0010] A coil is proposed comprising a tube with a tube wall made of an electrically conductive material, wherein the tube has an inductive section in which a gap is arranged in the tube wall that forms the tube wall in the inductive section into a helix, and wherein the tube has at least one contact section comprising a connection area and at least one terminal area, wherein the connection area has the same contour as an adjacent section of the helix, and the terminal area forms an electrical terminal of the coil, the connection area electrically connecting the terminal area to the inductive section.

[0011] A tube can be defined as an elongated hollow body having an opening that extends from a first end through the entire body to a second end opposite the first end. The tube can be symmetrical about its longitudinal axis, which extends from the center of a base at the first end to the center of a base at the second end. In one embodiment, the tube can have a circular, oval, or rectangular cross-section. However, other cross-sections are also possible.

[0012] A helix can be defined as a helical structure. The helix can, in particular, form turns of the coil.

[0013] The tube may, in particular, have a helical slit in its wall, through which the coil windings are formed. The tube is made of a conductive material. A conductive material is defined as one with a conductivity greater than 10⁴ S / m, but especially those with a conductivity greater than 10⁵ S / m or greater than 10⁶ S / m. Materials with very high conductivity, such as metals like copper, aluminum, silver, or gold, can be suitable. Industrial steels such as carbon steel, stainless steel, alloy steel, or tool steel can also be suitable as the starting material for the tube.

[0014] The tube comprises an inductive section and at least one contact section. The inductive section can generate inductance through the helix formed by the gap. The inductive section and the contact sections are formed integrally from the same material as the tube wall. Therefore, no joining materials, such as solder, are required to connect the inductive section to the contact section. Instead, the inductive section and the contact section can be formed by appropriate structuring of the tube wall and remain connected to each other through the tube material.

[0015] The coil has the advantage that no internal connections are required to link an inductor to a terminal. Instead, the inductive and contact areas can be integral. This coil exhibits a lower overall resistance than one requiring internal connections. Furthermore, the elimination of internal contacts also removes the thermal and mechanical stresses that would otherwise occur at these contacts, thus reducing the coil's susceptibility to failure.

[0016] The pipe does not need to be round in cross-section; it can be oval, square, rectangular, polygonal, square with rounded corners, rectangular with rounded corners, or polygonal with rounded corners, for example. A square cross-section offers the advantage of optimal use of the available installation space for a given height or width.

[0017] Depending on the intended application of the coil, the base of the tube can be planar, meaning the tube's dimensions spanning the base are large compared to its height, and the height itself can be small. Alternatively, the tube can have a small base but a considerable height. For example, if the coil is mounted on a circuit board in a narrow enclosure, a planar and flat shape may be advantageous. Conversely, if space on the circuit board itself is limited, a tube shape with a small base but a significant height might be more suitable.

[0018] The connection area has the same contour as the adjacent section of the winding. Therefore, deformation of the connection area, which would be transferred to the directly connected helix, is avoided. Deformation refers specifically to bending and embossing. Such a force acting on the connection area directly acts as a bending moment on the inductive section and leads to deformation of the helix. The pitch of the helix, meaning the regularity of the turns and the gaps in the helix, can deteriorate even with a small force acting on the connection area. For example, a helix can thus exhibit a narrower gap on one side and a wider gap on the opposite side.A stronger force applied in the connection area can easily cause a short circuit in the helix, as turns of the helix, especially those near the connection area, can be bent together and then touch.

[0019] The contour is understood to be the external shape that the section or segment of the helix exhibits when viewed in a direction parallel to the longitudinal axis of the pipe. For example, if the pipe is rectangular and the connection segment is located on a straight side of the rectangle, then the connection segment is also straight. If the adjacent segment of the helix has a corner, the contour of the corner must also be present in the connection segment. In the case of a round pipe, the connection segment accordingly has the contour of a circular segment. An adjacent segment of the helix and the connection segment, which have the same contour, can be arranged parallel to each other.

[0020] A transition from the connection area to the inductive section can be straight along one direction of the tube's longitudinal axis. Avoiding a kink or angle between the connection area and the inductive section prevents weakening of the material at this point, thus preventing breakage. Furthermore, a straight transition avoids any change in the path or curvature of the flowing current, thereby preventing unintended inductances in the coil.

[0021] Preferably, the inductive section should not exhibit any deformation. Since the connection area has the same contour as the adjacent section of the helix, deformation of the connection area, and thus the application of force to it, can be avoided. Applying a force to the connection area, which also leads to deformation of the connection area, can easily cause deformations within the helix itself. Even a small deformation of the inductive section can lead to changes in the pitch, which characterizes the ratio of helix to gap and the regularity of the helix turns, and to variations in the electrical properties of the coil, causing it to no longer meet the intended requirements. More severe deformations can compress individual turns of the helix, potentially even leading to a short circuit in the coil.A short circuit between two turns does not necessarily lead to a non-functional coil; however, the short-circuited turn would not contribute to the inductance of the coil without a current flowing through it.

[0022] Furthermore, the connection area can be formed by deforming the tube wall. In this way, an integral design of the coil from the connection area up to and including the inductive section can be achieved, and the series resistance of the coil can be kept low.

[0023] The connection area and the joint area can be located in a plane perpendicular to a longitudinal axis of the tube. Connection areas arranged in this way do not increase the overall dimensions of the coil, since the connection area does not adjoin the joint area along the longitudinal axis of the tube. The overall coil length can thus be kept short relative to the helix, resulting in a favorable coil form factor.

[0024] Furthermore, the connection area can have a flat surface that forms a solderable connection. Accordingly, the coil can be designed specifically to be soldered onto a conductor track, for example, on a printed circuit board.

[0025] The inductive section can be separated from a mounting surface by a portion of the connection area. This offers the advantage of mechanical and thermal isolation of the inductive area from the mounting surface on which the coil is installed. This inhibits the transmission of coil vibrations or heat to a mounting surface, such as a printed circuit board. The coil's magnetic field is also less affected by a separated mounting surface, thus ensuring that the coil exhibits the expected electrical properties. In an embodiment where the coil can be surrounded by or embedded in a magnetic material, separating the coil from the mounting surface ensures that sufficient magnetic material can be positioned between the coil and the mounting surface.In this way, the coil can be evenly enveloped by the magnetic material, creating a uniform magnetic field around the coil and additionally protecting the coil from all sides.

[0026] Spacing of the inductive section can be achieved, for example, using L-shaped connection areas. A vertical portion of the L-shaped connection area acts as a spacer, while a horizontal portion provides the flat surface for electrical contact. The vertical portion of the connection area separates the inductive section of the coil from a mounting surface, such as a printed circuit board, to which the coil can be electrically connected via the horizontal portion.

[0027] Furthermore, the coil can have a magnetic core. An application e.g.A ferromagnetic core can provide a higher magnetic flux density in the coil and increased coil inductance. Suitable core materials include nickel-zinc, manganese-zinc, and cobalt, as well as other alloys. The core is not limited to those located solely within the coil but also includes cores that form an integral part of a modular coil housing. A coil with a modular housing can improve the coil's electromagnetic compatibility (EMC). For example, using an EP core as the housing can enhance electromagnetic shielding, particularly in high-frequency applications, thereby increasing EMC.

[0028] Furthermore, the tube can be embedded in a plastic to protect it primarily against mechanical damage, but also against temperature and chemical influences. Suitable plastics include epoxy resin, phenyl resin, and silicone. Embedding the tube in a plastic makes the coil component more suitable for assembly using a pick-and-place machine, for example.

[0029] Powders with magnetic properties, such as iron powder, or magnetic nanoparticles can be mixed into the plastic. Adding magnetic particles to the plastic increases the coil's inductance and improves its electrical properties. The inductance can be adjusted by varying the proportion of magnetic particles in the plastic. Furthermore, even when embedded in a plastic, regardless of whether the plastic contains magnetic powder, the coil can have a magnetic core to increase its inductance. Embedding the coil in a plastic, especially one containing a powder with magnetic properties, can improve the electromagnetic shielding of the component, particularly in high-frequency applications, and enhance electromagnetic compatibility.

[0030] Furthermore, the coil can have an outer diameter of 0.2 to 50 mm. Preferably, the outer diameter of the coil can be in the range of 0.5 to 20 mm. This size is particularly suitable for providing coils that are suitable for applications on a printed circuit board. The outer diameter should not be less than 0.2 mm, preferably not less than 0.5 mm, as otherwise such a small coil would be produced that automated parts handling would be associated with considerable technical difficulties. The outer diameter should not be greater than 50 mm, preferably not greater than 20 mm, as otherwise manufacturing the coil from a tube would be uneconomical.

[0031] The invention relates to a module comprising at least two coils. These coils can be, in particular, those described above. The at least two coils are arranged in a common housing formed by a plastic material in which both coils are embedded. The two coils are arranged spatially parallel to each other.

[0032] Preferably, the coils are arranged so that they can be individually electrically connected and are not interconnected within the module. In an alternative embodiment, the coils can be electrically connected in parallel or in series to give the entire module a desired inductance.

[0033] In this way, it is possible to assemble a module from several coils in such a way that the entire module has a higher or lower inductance than the individual coils.

[0034] Using the module can shorten the assembly time of a printed circuit board with a large number of coils, thus reducing cycle times in a manufacturing process. By mounting the module instead of numerous individual coils, only one module needs to be positioned on the circuit board during assembly, for example, using a pick-and-place machine. The module can therefore simplify subsequent processes in which it is installed.

[0035] Furthermore, arranging multiple coils within a single module saves space compared to placing several individual coils side by side. In applications where available space is very limited, such as on a circuit board for a mobile device like a smartphone, this space saving can be a significant advantage. Additionally, using the module instead of individually embedded coils allows for savings in housing material.

[0036] Another aspect of the present application concerns a method for manufacturing a coil. The coil may in particular be the coil described above.

[0037] The process includes the following steps: a. Providing a pipe with a pipe wall made of an electrically conductive material, and b.Creating a gap in an inductive section of the tube, wherein the gap in the inductive section forms the tube wall into a helix, and forming at least two sections of the tube into contact sections, c. Deforming a first part of the contact sections into at least one connection area, wherein a second part of the contact sections retains the shape of the tube wall and forms a connection area, the connection area electrically connecting the connection area to the inductive section.

[0038] The inductance of the inductive section can only be created by generating the gap. This gap can be a cutting gap created with a laser. The shape of the contact section can also be generated with a laser, particularly in a laser process that combines the creation of the gap with the laser cutting process.

[0039] A laser process is suitable for creating the gap in the inductive sections, as well as for creating a recess in the contact sections of the tube. The laser process offers the advantages of flexibility and speed. Furthermore, it does not generate any mechanical stress, as it operates without contact and leaves minimal residue. Other alternatives for creating the gap include milling, sawing, or waterjet cutting.

[0040] The aforementioned step b. The process can include a further sub-step in which a recess is formed in the contact section of the tube by removing a portion of the tube wall. The recess in the contact section of the tube and the gap in the inductive area can be created together in a single process step.

[0041] Accordingly, the entire step can b.produced in a single process step, for example by laser cutting.

[0042] Furthermore, in step c. The connection area is formed by deforming the first part of the contact section in a direction perpendicular to the longitudinal axis of the tube. Since the connection area is not deformed in any direction along the longitudinal axis of the tube, this deformation does not lengthen the coil. By having a connection area that extends predominantly in a direction perpendicular to the longitudinal axis of a tube, it is possible to avoid excessively increasing the overall coil length compared to the length of the inductive section or the helix.

[0043] Furthermore, in step c.The first part of the contact sections is formed into a connection area by a stamping process. Forming, such as bending or embossing, using a stamping process is efficient, reliable, and reproducible.

[0044] A second part of the contact sections, which can become the connection area during the stamping process, can be supported by a counter-punch or a support surface during the stamping process, so that no bending forces act on this second part. The counter-punch can be shaped to match the contour or outer form of the tube. Since no bending moment acts on the connection section, the connection area retains the contour of the tube wall from which it is formed and is therefore identical to the contour of the adjacent inductive section. This also prevents any force acting on the inductive section that would lead to undesirable deformation. Even slight deformation of the inductive section can alter the electrical properties of the coil.A greater force applied to the connection area can even lead to a short circuit in the inductive region, as two adjacent windings of the helix may touch as a result of the force. By eliminating a bending moment in the connection area, the electrical properties of a coil produced using the aforementioned process become more reproducible and predictable.

[0045] Additionally, in step b. First, a coil strand is created by generating several inductive sections along the tube, each containing a gap that forms the tube wall into a helix, and a contact section is formed between each pair of inductive sections. In step c.A first part of the contact sections can be formed into at least one connection area, and a second part of the contact sections can retain the shape of the tube wall and form a connection area, the connection area electrically connecting the connection area to the inductive section.

[0046] Such a coil assembly optimizes coil handling in production. Multiple coils can be processed simultaneously, which in turn can lead to shorter cycle times. Furthermore, creating multiple inductive sections within a single tube can save material.

[0047] Additionally, the connection area can be formed by deforming the pipe wall in a direction perpendicular to the pipe's longitudinal axis. Deforming the pipe wall to create a connection area in a direction perpendicular to the pipe's longitudinal axis allows for the formation of a connection area without causing any change in the length of the coil strand, whether through stretching or compression. Deformation in a direction parallel to the longitudinal axis would inevitably result in a change in the coil strand's length. Therefore, a coil strand formed in this way retains its defined overall length despite the forming process for the connection area. Handling of the coil strands is improved because the same dimensions and thus consistent conditions can be assumed in various production steps within the process line.Especially in the manufacturing process, a consistent length of the coil strands throughout the entire production is advantageous, as no additional measurements or new input of the framework conditions are necessary in various production steps, such as the singulation of the coil strand.

[0048] Additionally, in the next step d. The coil strand is separated perpendicular to the longitudinal axis of the tube between two inductive sections. A coil strand can then be subsequently divided into several coils. The coils can be individually divided so that only one inductive section with two adjacent contact sections is created. However, it is also possible to separate several inductive sections, each held together by a contact section, from the coil strand to form a suitable overall coil consisting of several individual coils.

[0049] Multiple coils or coil strands can be embedded in plastic to form a package. The coils or coil strands can already have a magnetic core at this point. It is advantageous to arrange the coil strands parallel to each other before embedding. Embedding multiple coil strands simultaneously, rather than individually, accelerates the manufacturing process. The plastic protects the coils from mechanical, temperature, and chemical influences. Powders with magnetic properties or magnetic nanoparticles can also be mixed into the plastic. Adding magnetic particles to the plastic increases the coil's inductance, which can be adjusted by varying the proportion of magnetic particles in the plastic.

[0050] It can be advantageous to arrange magnetic cores within the coil strands or coils. This can increase the inductance of the coils or coil strands. Furthermore, arranging the cores within the coil strands before embedding them in a plastic allows for the production of coils with a magnetic core embedded in a plastic that may also contain magnetic components. This can increase the inductance and electromagnetic compatibility of the coils.

[0051] After embedding several parallel coil strands in a package, the coils can be separated both transversely and parallel to the longitudinal axis of the coil strands. It is advantageous to guide the separation line through the contact sections of the coils. This separates the package into individual coils. It is possible to separate the package first transversely and then parallel, or vice versa.

[0052] The invention relates to a method for manufacturing a module. The package, which comprises several parallel coil strands, can be separated transversely to the longitudinal axis of the strands. In this option as well, it is advantageous to guide the separation line through the contact sections of the coils. Separated coils parallel to the axis are not produced.

[0053] The module comprises at least two coils in a common housing, the tube having a contact section divided into a connection area and a terminal area. The method for manufacturing the module comprises the following steps: Generating at least two coil strands by creating several inductive sections along each of the tubes, in each of which a gap is created that forms the tube wall into a helix in the respective inductive section, and wherein a contact section is formed between each pair of inductive sections, and wherein a first part of the contact sections is formed into at least one connection area, and wherein a second part of the contact sections retains the shape of the tube wall and forms a connection area, the connection area electrically connecting the connection area to the inductive section, arranging the coil strands in parallel, embedding the coil strands in a plastic that forms the housing, and separating the coil strands connected by the plastic along separation lines that run transversely to a longitudinal axis of the coil strands to the module.

[0054] The invention will now be described in more detail with reference to schematic representations of exemplary embodiments. Figure 1a shows a spatial representation of a possible embodiment of a pipe. Figure 1b shows a spatial representation of a possible second embodiment of a pipe. Figure 2 shows a spatial representation of a coil strand. Figure 3 shows a spatial representation of an intermediate product in the production of a coil from the coil strand. Figure 4 shows a spatial representation of a coil according to an embodiment of the invention. Figure 5 shows a spatial representation of several coil strands embedded in plastic to form a package. Figure 6 shows a spatial representation of a coil embedded in plastic, which is a ready-to-use individual component.

[0055] Identical, similar, or seemingly identical elements are marked with the same reference symbols in the figures. The figures and their proportions are not to scale.

[0056] In Figures 1a and 1b A tube 2 is shown with one round and one rounded square cross-sectional area. The tube 2 is an elongated hollow body having an opening that extends from a first end of the body through the entire body to a second end opposite the first end. The tube 2 can be symmetrical about its longitudinal axis 3, with the longitudinal axis 3 extending from the center of the base at the first end to the center of the base at the second end. In one embodiment, the tube 2 can have a circular, oval, rectangular, or polygonal cross-sectional area. Other cross-sectional areas are also possible.

[0057] The tube 2 can have an outer diameter of 0.2 to 50 mm. Preferably, the outer diameter of the tube 2 can be in the range of 0.5 to 20 mm. This size is particularly suitable for manufacturing coils 1 that are suitable for applications on a printed circuit board. The tube wall 6, The thickness of which is determined by the distance between the inner and outer radii of the tube 2 can vary considerably depending on the tube 2 used, with a thickness of less than 1 mm being advantageous for machining. The outer surface 5 of the tube runs along the outer radius in the direction of the longitudinal axis 3. 2. Pipe 2 consists of a primarily electrically conductive material.

[0058] Tube 2 represents a starting material used in the production of a coil 1. During the manufacturing process, the material can be... Figure 1a The pipe 2 shown is first structured into a coil strand. Figure 2Figure 1 shows the coil assembly. The tube 2 can be structured, in particular, by a laser process in which inductive sections 7 and contact sections 8 are formed within the tube 2. The inductive sections 7 and the contact sections 8 alternate along the length of the tube 2.

[0059] In the inductive sections 7, a gap 4 is created that penetrates a tube wall 6 and forms the tube wall 6 into a helix. This creates an inductance in the inductive sections 7. During the manufacturing process, part of the contact sections 8 is transformed into a connection area 11, while another part of the contact section becomes a connection area 10. A recess is formed in the contact sections 8 during the structuring of the tube 2, whereby a portion of the tube wall 6 is removed.

[0060] The coil assembly optimizes the handling of the coils 1 in production. This allows multiple coils 1 to be processed simultaneously, resulting in shorter cycle times. Furthermore, creating multiple inductive sections 7 within a single tube 2 allows for material savings.

[0061] The inductive sections 7 are integrally connected to each other by the contact sections 8 and have no unnecessary contact resistances between them.

[0062] The different inductive sections 7 of the coil strand can have different or the same inductances. Thus, it is possible to create different coils 1 from a tube 2, each with a variable inductance, making them suitable for a wide variety of applications. The inductances can be varied, for example, by the number of turns formed with the gap 4, or by the distance of the gap 4 along the longitudinal axis 3 after one revolution around the tube. 2, which corresponds to the width of the coils, can be varied. In the exemplary embodiment from Figure 2 The columns shown in column 4 are the same, and consequently the inductance of the individual inductive sections 7 is also the same.

[0063] In Figure 3A spatial representation of an intermediate product in the manufacture of a coil 1 from the coil strand is shown. The coil strand was separated along separation lines 12, which run transversely to the longitudinal axis 3 of the coil strand.

[0064] The coil 1 has a tube 2 made of electrically conductive material, with a gap 4, which runs along a surface 5 and around the longitudinal axis 3 of the tube 2, thus forming an inductive section 7. In an alternative embodiment, the entire tube 2 can be structured such that only a single inductive section 7 and two adjacent contact sections 8 result. Accordingly, the tube 2 can be configured as described in Figure 3The intermediate product shown is structured by cutting the tube 2 to a suitable length. The contact section 8 and the inductive section 7 are directly connected to each other. The contact section 8 and the inductive section 7 are integrally and integrally formed from the structured tube wall 6.

[0065] Figure 4 The coil 1 is shown after a first part of the contact sections has been bent into two connection areas 11 using a stamping process, with an undeformed second part of the contact sections forming the connection area 10. For this purpose, the second part of the contact sections was supported during the stamping process by a counter-punch or a support surface to prevent bending forces or moments from acting on the second part during the stamping process. Preferably, the counter-punch is shaped to match the contour or outer form of the tube. 2.Due to the lack of a bending moment on the connection area 10, the connection area 10 remains unchanged and has the same contour of the pipe wall 6 as the contour of the adjacent inductive section.

[0066] Since the force exerted by the stamping process in the connection area 10 is neutralized by the counter-punch during the forming of the first part of the contact sections to the connection area 11, no bending moment acts on the adjacent helix. Thus, the helix retains its shape and pitch, and possible short circuits between adjacent turns can be ruled out.

[0067] In the embodiment described in Figure 4As shown, the connection area 10 has the shape of a circular segment, since the tube 2, from which the coil 1 was made, is circular. In an embodiment where the tube 2 has a rectangular base, the connection area 10 could, for example, have a straight contour. However, this does not limit the shape of the connection area 10. Rather, the connection area 10 can have any shape and contour that is similar to that of the tube 2 in an adjacent section.

[0068] Connection area 11 in Figure 4 was caused by a deformation of the pipe wall 6,in a direction perpendicular to the longitudinal axis 3 of the tube 2. The deformation to form a connection area 11 in a direction perpendicular to the longitudinal axis 3 of the tube 2 allows the connection area 11 to be formed without causing a change in the length of the coil strand, whether elongation or compression. A deformation in a direction parallel to the longitudinal axis 3 would inevitably result in a change in the length of the coil strand. If the connection area 11 were, for example, to be deformed in the direction of the longitudinal axis 3 of the tube 2 (in Figure 4(as shown in the diagram), a coil strand with several such sections would be shortened due to deformation. However, if the connection section 11 is bent perpendicular to the longitudinal axis 3 of the tube 2, a coil strand formed in this way retains its defined overall length despite the forming process for the connection section 11. This improves the handling of the coil strands, especially during the manufacturing process, because the same dimensions and associated parameters, such as the position of the inductive sections, can be assumed in various production steps of the process line. For example, when separating the coil strand, a central cut between two inductive sections can be made automatically and without further measurements.

[0069] Another advantage of arranging the connection areas 11 perpendicular to the longitudinal axis 3 of the tube 2 is that the total coil length, especially compared to the length of the helix, can be kept short in order to achieve a better form factor for the coil 1.

[0070] Furthermore, the inductive section, which is in Fig. 4In the illustrated embodiment, the inductive section 7 is L-shaped and spaced from the mounting surface by a portion of the connection area 11. This mechanically and thermally isolates the inductive section from the mounting surface. This inhibits the transmission of vibrations from the coil 1 or heat to the mounting surface, which could be a printed circuit board, for example. Additionally, the distance between the inductive section 7 and the mounting surface provides sufficient space to completely embed the inductive section in a plastic material 9. Furthermore, the magnetic field of the coil 1, and consequently its inductance, is less affected by the spaced mounting surface.

[0071] A horizontal part of the in Fig. 4The L-shaped connection area 11 shown forms a flat surface that provides a solderable connection. This allows the coil 1 to be soldered onto a conductor track, for example, on a printed circuit board. The integral design of the coil 1 from the tube 2 eliminates the need for additional connection techniques. Consequently, the coil 1 has a lower overall resistance, which in turn results in lower power loss. Furthermore, the thermal stress, especially at potential contacts, is also reduced, thus decreasing the coil 1's susceptibility to failure.

[0072] In Figure 5Four coil strands are embedded in plastic 9, with the longitudinal axes 3 of the coils 1 arranged parallel to each other. Such an arrangement is also called a package. Here, the four coil strands each have four inductive sections 7 and four contact sections 8. The package shown in Figure 7 is merely an example, and more coil strands, and in particular more than 20 coil strands, with any other number of inductive sections 7 and contact sections 8 can be used. In this embodiment, the contact sections 8 are opened by recesses and then stamped to form an undeformed connection area 10 and two terminal areas 11. The dashed lines indicate several possible separation lines 12, which run transversely or parallel to the longitudinal axis 3 of the coils 1 and through the contact sections 8.Alternative embodiments are also conceivable in which singulation occurs along any other number of separating lines 12. If the coil 1 is singulated parallel to the longitudinal axis 3 of the tube 2, the inductive sections 7 are connected in series. By embedding several coil strands simultaneously, rather than individually, the manufacturing process can be accelerated.

[0073] The plastic 9 acts as a kind of housing, providing protection against potential hazards from the immediate environment. The protective function of the plastic can be pragmatically enhanced by adding particles with desired magnetic properties. The inductance can also be adjusted by varying the quantity or concentration of the magnetic particles in the plastic. In an alternative embodiment, a coil 1 could be connected to an EP core, which also integrally forms a housing. The EP core could consist of two halves that can subsequently be bonded together. An EP core allows the coil 1 to be electromagnetically shielded, particularly in high-frequency applications, thus increasing the electromagnetic compatibility of the component.

[0074] Creating a module containing multiple coils 1 within a single package is also easily possible. This involves creating a package, as shown in Fig. 5 shown, depending on requirements, parallel and / or perpendicular to the longitudinal axis 3 of the pipe 2. The in Fig. 5 The package shown is merely an example and significantly longer coil strands, with more coils 1, and a larger number of coil strands can be arranged in the package.

[0075] The contact surfaces of a module itself can be contacted from below and, if necessary, from the side, and can be connected, for example, via solder pads or conductor tracks using a soldering or adhesive bonding process. Using a module can lead to a reduction in cycle time during the assembly of coils 1. By installing a module instead of individual coils 1, a pick-and-place machine, for example, only needs to position the component on a circuit board once instead of multiple times. Furthermore, arranging several coils 1 within a module saves space compared to arranging several individual coils 1 side by side.

[0076] The coils 1 in the module can be configured to be connected in parallel, in series, or not at all. In an embodiment where several coils 1 are arranged side by side, each coil 1 can be individually connected. If, however, such a module is connected by two conductor tracks running perpendicular to the longitudinal axis 3, the inductive sections 7 can be electrically connected in parallel. If the conductor track is laid in a meandering pattern under the module, the inductive sections 7 can be connected in series. Thus, the coils 1 themselves, within a single module, can be interconnected in a variety of ways, both with each other and within an electronic device.

[0077] Figure 6Figure 1 shows a single coil 1 embedded in plastic 9. The contact section, comprising a circular segment-shaped connection area 10 and two L-shaped connection areas 11, is located at the end face of the embedded coil 1. The coil 1 can be produced either by separating the coils 1 from a package or by embedding a single coil 1, as shown in Figure 9. Figure 4 , made of plastic 9. Reference symbol list

[0078] 1 Coil 2 Tube 3 Longitudinal axis 4 Gap 5 Sheath surface 6 Tube wall 7 Inductive section 8 Contact section 9 Plastic 10 Connection area 11 Terminal area 12 Separation lines

Claims

1. Method for producing modules, each of which has at least two coils (1) in a common housing, comprising the steps of: - creating at least two coil strands by creating a plurality of inductive portions (7) along each of two tubes (2), a gap (4) being created in each of the inductive portions which forms a tube wall (6) in the respective inductive portion (7) into a helix, and wherein a contact portion (8) is formed between each two inductive portions (7), and wherein a first part of the contact portions (8) is formed to create at least one connection region (11) in each case, and wherein a second part of the contact portions (8) maintains a contour of the tube wall (6) and forms a connecting region (10), wherein the connecting region (10) electrically connects the connection region (11) to the inductive portion (7), - arranging the coil strands in parallel, - embedding the coil strands in a plastic (9), which forms the housing, - separating the coil strands connected by the plastic (9) along separating lines (12) which run perpendicular to a longitudinal axis (3) of the coil strands and between inductive portions (7) to form the module.

2. Method according to Claim 1, wherein a laser process is used to create the gap (4) and to shape the contact portions (8).

3. Method according to either of Claims 1 and 2, wherein a recess is formed in the contact portions (8) of the tube (2) by removing a region of the tube wall (6).

4. Method according to Claim 3, wherein the recess in the contact portions (8) of the tube (2) and the gap (4) in the inductive portion (7) are created jointly in a single method step.

5. Method according to Claims 1 to 4, wherein the connection regions (11) are each formed by deformation of the first part of the contact portion (8) in a direction perpendicular to the longitudinal axis (3) of the tube (2).

6. Method according to any of Claims 1 to 5, wherein the first part of the contact portions (8) is shaped by a punching process with a counter punch to form the connection region (11).

7. Method according to Claim 6, wherein the second part of the contact portions (8), which as a result of the punching process becomes the connecting region (10), is supported by the counter punch during the punching process, so that no bending forces act on the second part during the punching process.

8. Method according to any of Claims 1 to 7, additionally comprising the following step of: separating the coil strands parallel to a longitudinal axis (3) of the coil strands.

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