Coil winding type, inductive component, and method for adjusting inductance

Abstract

The coil former (1) for the inductive component (7) comprises a base body (2) wound in a partial area with an electrically insulating foil (3). The inductive component (7) comprises the coil former (1) and a winding (8) wound around the coil former, whereby the electrically insulating foil (3) is disposed between the base body (2) and the winding (8). In the method for adjusting the inductance, the length of the electrically insulating foil (3) is selected according to the target value of the inductance.

Description

Technical Field

[0001] The present invention relates to a coil winding type for an inductive component and an inductive component including a coil winding type having a winding of a winding wire. This can be an air-core coil, that is, a coil without a magnetic core. The inductive component is used particularly in a stereo system.

Background Art

[0002] In many applications, it is desirable to accurately adjust the inductance value of a component, at least by the statistical average of a group of inductances (lots). Particularly in resonance applications, high-precision inductance adjustment is required.

[0003] Geometric dimensions greatly affect the inductance of an electrical component, particularly in the case of an air-core coil. A high-precision inductance value can be generated only within specific physical limits and requires precise control of the geometric shape. For inductances with or without a ferrite core, variations in material properties and operating temperature also lead to variations in the inductance value. Correcting the deviation of the inductance value of a finished component from a desired target value is called "adjustment" or "to adjust".

[0004] German Patent Application Publication Nos. 36 18 122 A1, 39 26 231 A1, 199 52 192 A1, and 10 2008 063 312 A1 describe adjustable inductive components. Adjustment is usually achieved by forcibly inserting and removing a core of a soft magnetic material into or out of the winding, or by separating or compressing the winding.

[0005] An object of the present invention is to provide an improved coil winding type, an improved inductive component, and a method for adjusting the inductance of an inductive component.

Summary of the Invention

Means for Solving the Problems

[0006] According to a first aspect of the present invention, the coil form is configured as a carrier for the winding of the inductive component. The coil form comprises a base body, at least a part of which region is wound with an electrically insulating foil. The diameter of the coil form is selectively increased by winding with the foil. Therefore, after the winding is wound on the coil form and over at least a part of the region of the foil, the inductance can be adjusted in a standardized manner.

[0007] In one embodiment, the base body of the coil form is made of a non-magnetic material. This can be, for example, a plastic material. Therefore, the inductive component can be configured as an air-core coil, that is, without a magnetic core around which the winding is wound. Therefore, the coil form functions purely as a carrier for the winding and does not induce magnetic flux. In such an embodiment, the inductance depends particularly greatly on the geometric shape, particularly on the diameter of the coil, whereby precise fine-tuning by changing the diameter is possible.

[0008] For example, the thickness of the foil is significantly smaller than 1 mm. The maximum thickness of the foil is, for example, 100 μm. The thickness of the foil can particularly be 10 - 40 μm.

[0009] In an alternative embodiment, the base body can be made of a magnetic material. This can be, for example, a ferrite core.

[0010] The foil is wound, for example, helically around the base body. The length of the foil and, therefore, also the number of turns of the foil around the base body (when the winding geometry is defined) can be defined according to the target value of the inductance. For example, the number of turns varies between 1 and 4 turns.

[0011] The foil is arranged in such a way that the winding of the coil can be placed outside the winding of the foil in particular. In particular, the geometric shape of the winding of the foil corresponds to the geometric shape of the winding of the coil, and it is preferable that the winding of the foil is shorter than the winding of the coil. The winding of the coil can cover the entire length of the foil and can extend beyond the foil. The winding can also cover the entire width of the foil.

[0012] In the following, the maximum possible effective length is the length of the foil where the foil is present under the entire winding. Therefore, the entire winding is applied to the outside of the enlarged diameter.

[0013] The foil is applied, for example, in a first step, to half of the maximum possible effective length, then the winding is applied and the inductance of the component is measured. Thereafter, depending on the measured inductance value, the length of the foil is decreased or increased for the manufacture of further components. The initial application of the foil over only a part of the maximum possible length, for example half, is intended to provide flexibility for fine-tuning the length of the foil.

[0014] The foil in the resulting component does not extend over the entire length of the base body, for example, in particular, does not extend over the maximum possible effective length of the foil. For example, the foil extends over less than two-thirds of the length of the base body, or over the maximum possible effective length. Or the foil extends over at least one-third of the length of the base body, or over the maximum possible effective length. Also, initially, or in the adjusted component, it is possible to extend the foil over the entire maximum possible effective length, or to make it foil-free.

[0015] Alternatively, or in addition, it is optionally possible to adjust the diameter (and thus the inductance) by varying the thickness of the foil or the number of layers of the foil. The foil can be applied to the base body in a single layer. However, in order to further vary the thickness, the foil can also be applied in multiple layers. To adjust the inductance, for example, a specific number of foil layers are initially present, and then one or more layers are removed or added depending on the measured inductance value. The foil can also have different thicknesses, and the thickness of the foil can be varied for fine-tuning. For example, the foil always extends over the maximum effective length. As another method, a combination of changing the length and changing the number or thickness of the foil layers is also possible.

[0016] In one embodiment, the foil is made of a non-magnetic material. This can be, for example, a plastic material. The foil can include the same material as the coil winding type. Therefore, the foil only functions to increase the diameter of the coil winding type and does not induce magnetic flux.

[0017] The coil winding type can include a recess in which the foil is disposed. The recess is configured for the accurate positioning of the foil and / or the accurate positioning of the winding.

[0018] The configuration of the recess is, for example, circumferential. In particular, the recess extends helically around the base body. The recess can extend section by section or continuously only circumferentially around the base body. For example, the recess has at least two turns, especially continuous turns. The recess extends, for example, at least over the entire length of the foil. The recess is preferably configured not only for positioning the foil but also for positioning the winding. The recess preferably extends over most of the length of the base body.

[0019] The recess has a lateral limiting part, so that the foil and / or the winding is guided in a non-sliding manner perpendicular to its progression in the main direction of its expansion. The lateral limiting part can be formed by the material of the base body. The recess can in particular be formed directly during the manufacture of the base body, for example during an injection molding process. It is also possible that there is only one lateral limiting part for positioning.

[0020] The foil is, for example, slightly wider than the recess. The foil can also have the same width as the recess or can possibly be slightly wider than the recess. In this case, the foil can be fixed in the recess by clamping.

[0021] According to a further aspect of the invention, the inductive component comprises the aforementioned coil winding type and a winding wound around the coil winding type. In at least some regions, in particular over the length region of the winding, the foil is arranged between the winding and the base body. As a result, at least some regions of the outer diameter of the coil winding type, and thus of the inner diameter of the winding, are increased. This results in an increase in the inductance of the component.

[0022] The winding is configured, for example, as a flat wire. As another option, the winding may be configured as a round wire. This can be a copper wire.

[0023] The inductance of the component is, for example, from 1 to 1000 nH. Depending on the design, it is possible to adjust the inductance in the range of up to 10% in steps of, for example, 0.1% by changing the length of the foil.

[0024] The winding preferably extends over the entire length of the foil and, for example, also preferably extends beyond the length of the foil. The foil and the winding are in particular configured as two uniform windings positioned one on top of the other. The wound winding is preferably longer than the foil. Therefore, the winding covers only a part of the foil in the main direction of the extension of the foil. For example, the ends of the winding extend beyond the foil on both sides.

[0025] The winding preferably has more turns than the foil. The number of turns of the foil is, for example, at most two-thirds of the number of turns of the winding. For example, the winding has 8 turns and the foil has 5 turns. Therefore, it has sufficient flexibility to finely adjust the inductance.

[0026] As a result, the diameter of the winding of the turns can be different in different regions. The diameter is particularly larger where the winding is disposed outside the foil.

[0027] According to one embodiment, the inductive component comprises a coil winding type having a recess, and at least a partial region of the foil and the winding is disposed within the recess. The recess can in particular be configured as already described above for the coil winding type. The recess can in particular be helical and can have at least 2 turns. The winding can be slightly narrower than the recess. The winding can also have the same width as the recess or can possibly be slightly wider than the recess. In this case, the winding can be fixed within the recess by clamping.

[0028] As another method, the foil can also be glued to the base body. For example, the foil is adhesive. The foil can also be attached to the base body by an applied adhesive. Similarly, the winding can be glued to the base body. For example, by gluing the foil to the winding, it is also possible to first attach the foil to the winding and then dispose and attach the winding together with the foil on the base body.

[0029] As another method, the winding and / or the foil can also be attached to the base body by hot caulking. In this process, after the foil and the winding are placed in the recess, pressure and heat can be used to expand the region protruding radially of the limiting part, whereby the foil and the winding are at least partially enclosed by the radial limiting part. Here too, the foil can first be attached by gluing and then the winding can be attached by hot caulking.

[0030] According to a further aspect of the present invention, a method for adjusting the inductance value of an inductive component is provided. In this case, at least a part of the region of the coil-wound base body is wound with foil. The length of the foil is selected according to the target value of the inductance. With a fixed geometric shape, the length corresponds to the number of turns of the foil.

[0031] Next, the coil-wound type is wound using a winding wire, whereby the foil is arranged between the base body and the winding wire in at least a part of the region, particularly along the region of the winding wire. The coil-wound type and the inductive component are configured as described above, for example.

[0032] To adjust the length of the foil, for example, the inductance of an inductive component of the same design is measured. It is also possible to measure the inductance indirectly, which is a different parameter that is a measure of the inductance. Then, the length of the foil for a further inductive component can be changed according to the deviation of the measured value from the target value.

[0033] The length is gradually increased or decreased, for example, until the desired target value is reached. For example, the number of turns is changed in the range of 1.00 to 4.00 turns. The increment of the length change is less than 1 turn, for example, 0.01 turn.

[0034] According to a further aspect of the present invention, a coil-wound type for an inductive component includes a limiting part for positioning the winding wire.

[0035] The limiting part is particularly configured to guide the section of the winding wire in the central region of the winding, that is, this is the section adjacent to both sides by at least one further turn of the winding wire. As a result, this is not the edge section of the winding. The section is guided to both sides through, for example, two limiting parts. Therefore, the limiting part forms a recess for accommodating at least one section of the winding wire.

[0036] The limiting part or the recess extends helically, particularly around the coil-wound base body. The limiting part or the recess comprises, for example, at least two windings. The recess can be configured within the coil-wound base body. The recess can also be configured to position the foil as described above. However, the coil-wound type can also be provided without the foil. In another way, the coil-wound type can be configured as described above.

[0037] According to a further aspect of the invention, the inductive component comprises such a coil-wound type having a recess in which the winding is arranged. The winding is configured, for example, as a flat wire. The foil can be arranged between the winding and the base body of the coil-wound type. Also, there may be no such foil. Otherwise, the inductive component can be configured as described above. The winding is attached to the base body as described above, for example, by clamping, gluing, or hot caulking.

[0038] The description of the subject matter provided herein is not limited to individual specific embodiments. Rather, the features of the individual embodiments can be combined with each other as long as they are technically reasonable.

[0039] For the subject matter described herein, based on examples of schematic diagrams, it will be described in more detail below.

Brief Description of the Drawings

[0040]

Figure 1

Figure 2

Figures 3A - 3E

Modes for Carrying Out the Invention

[0041] In the following figures, the same reference signs preferably refer to functionally or structurally equivalent parts of the various embodiments.

[0042] Figure 1 shows a coil winding type 1 for an inductive component. The coil winding type 1 is configured as a carrier for the winding.

[0043] The coil winding type 1 is particularly configured for an air-core coil, i.e., a coil without a magnetic core. The coil winding type 1 is non-magnetic. The coil winding type 1 may comprise a base body 2 made of plastic. The coil winding type 1 is produced, for example, by an injection molding process. The inductance of the air-core coil is mainly determined by the geometric shape of the turns.

[0044] In one alternative embodiment, the coil winding type 1 can also be configured as a magnetic core, for example, as a ferrite core, or there may be a magnetic core within the coil winding type 1.

[0045] The base body 2 in this case has a cylindrical shape. The base body 2 can also have a different shape, for example, a cubic shape. The base body 2 can also be part of a larger body, for example, part of an annular body. The base body 2 can be configured as a hollow body.

[0046] A partial region of the base body 2 is wound with a foil 3. The foil 3 functions to selectively increase the diameter of the base body 2.

[0047] The foil 3 is thin, which allows for fine-tuning of the diameter of the base body 2 and thus the inductance of the component after the winding is wound outside the foil 3. The foil 3 has a thickness of, for example, 10 μm to 40 μm. For example, the foil 3 has a thickness of 25 μm. In this case, the foil 3 is applied in a single layer.

[0048] The foil 3 contains a non-magnetic material. The foil 3 can contain a plastic material or be made of a plastic material. The coil winding type 1 and the foil 3 can be made of, for example, the same material. In other embodiments, the foil 3 can contain a magnetic material.

[0049] By selectively varying the length of the foil 3 corresponding to the number of turns k, it is possible to selectively adjust the region having an increased diameter, and thus to enable adjustment of the inductance of the resulting component. In this case, the foil 3 extends over k = 2.00 turns. For example, the number of turns of the foil 3 varies in the range of k = 1.00 to 4.00 turns. This change is carried out, for example, in 0.01 turn increments.

[0050] The coil winding type 1 further comprises recesses 4 configured for the precise positioning of the foil 3 and / or the winding 8. The more precisely the foil 3 and / or the winding 8 can be positioned on the coil winding type 1, the more precisely the inductance of the component can be adjusted.

[0051] The recess 4 extends circumferentially around the base body 2. In particular, the recess 4 extends helically around the base body 2 of the coil winding type 1. The recess 4 is delimited on both sides perpendicular to the circumferential direction by the limiting parts 5, 6. The limiting parts 5, 6 also extend around the base body 2. Therefore, the recess 4 is configured as a circumferential guide groove / channel. In other words, the recess 4 is configured as a helical groove and the limiting parts 5, 6 are configured as helical sides.

[0052] The foil 3 is placed in the recess 4. The width of the foil 3 is the same as the width of the recess 4. The foil 3 may be slightly narrower than the recess 4. The foil 3 can also have the same width as the recess 4 or a width slightly wider than the recess 4 and can be fixed in the recess 4 by clamping or gluing.

[0053] The winding 8 (see FIG. 2) can also have a width similar to the width of the recess 4. For example, the width b of the recess 4 is at most 25% larger than the width B of the winding.

[0054] The recess 4 comprises n turns, whereby in this case n = 8. It can also be less than 8 turns or more than 8 turns. The recess preferably comprises at least 2 turns.

[0055] In an alternative embodiment, the coil winding type 1 does not have the recess 4 for positioning the winding, but has the foil 3.

[0056] In a further alternative embodiment, the coil winding type 1 does not have the foil for increasing the diameter, but has the recess 4 for accurately positioning the winding.

[0057] FIG. 2 shows an inductive component 7 comprising a coil winding type 1 and a winding 8 wound therearound and thus forming a winding turn 9. The coil winding type 1 can be designed according to FIG. 1.

[0058] In this case, the winding 8 is configured as a flat wire. The main surface of the winding 8 is on the base body 2 of the coil winding type 1. Alternatively, the winding 8 can also be configured as a round wire. This is, for example, a copper wire.

[0059] The winding 8 in this case has m = 7.50 turns. Therefore, the possible maximum effective length of the foil 3 is likewise 7.50 turns. The winding 8 can also have more turns or fewer turns.

[0060] The winding 8 has two ends 10, 11. The ends 10, 11 continue, for example, for connecting the component 7 to a contact terminal (not shown), or further contact connections (not shown) are provided at the ends 10, 11.

[0061] A part of the region of the winding 8 is arranged outside the foil 3. Therefore, the foil 3 is arranged between the base body 2 of the coil winding type 1 and the winding 8. In the region where the winding 8 is arranged outside the foil 3, the diameter of the winding turn 9 is increased. Therefore, the winding 8 is arranged outside the foil 3 in some regions according to the length or the number of turns k of the foil 3, and is directly arranged on the base body 2 in some regions. Therefore, the diameter D of the winding turn 9 increases only in some regions. The inductance of the component 7 increases according to the size of the region having the increased diameter.

[0062] The winding 8 is arranged in the recess 4 for accurate positioning. The width B of the winding 8 may be slightly smaller than the width b of the recess 4. Therefore, the position of the winding 8 is accurately determined by the recess 4. The width B of the winding 8 may also be slightly larger than the width b of the recess 2 so that the winding 8 is fixed between the limiting parts 5 and 6 by clamping. The winding 8 can also be fixed in the recess 2 by high-temperature coking. The radially outer regions of the limiting parts 5 and 6 are particularly widened by high-temperature coking, whereby the winding 8 is at least partially surrounded radially outwards by the outer regions.

[0063] In one embodiment, as shown in FIG. 1, the inductive component 6 has no recess in the coil former 1 for positioning the winding 8, but has a foil.

[0064] In this case, the winding 8 is wound in one layer on the coil former 1. In other embodiments, the winding 8 can also be wound in multiple layers on the coil former 1.

[0065] In an alternative embodiment, the inductive component 7 has no foil between the base body 2 and the winding 8, but has a recess 4 for accurately positioning the winding 8. In this case, the diameter D of the winding 9 is uniform. Instead of having two limiting parts 5 and 6 in the recess 4, it is also possible to have only one limiting part 5 or 6 for positioning on one side. Furthermore, the recess 4 or the limiting parts 5 and 6 can also be formed only in sections.

[0066] Figs. 3A to 3E show method steps for adjusting the inductance of the inductive component.

[0067] According to FIG. 3A, a coil former 1 is provided. The coil former 1 can be configured like the coil former 1 in FIG. 1. The coil former 1 can be provided with a recess 4, but it is not necessarily required.

[0068] According to FIG. 3B, for example, based on the input measurement value “M” and according to the target value, the length l of the foil 3 is defined. The information can be obtained from the measurement of the inductance from the same inductive component. If the measured inductance is smaller than the desired target value, a foil 3 with a length l longer than the measured component is selected. If the measured inductance is smaller than the desired target value, a foil 3 with a length l shorter than the measured component is selected.

[0069] The length l of the foil 3 corresponds to the number of turns k for the specified coil winding type 1 and the geometric shape of the specified winding. The number of turns k varies, for example, in increments of 0.01 turns. For example, the number of turns is adjusted in the range of 1.00 to 4.00 turns.

[0070] According to FIG. 3C, the foil 3 is wound around the base body 2. In this case, the number of turns is set to approximately 2.05. The foil 3 can also be wound first and then cut to the desired length l. For accurate positioning, the coil winding type 1 can include a helical recess 4 (see FIG. 1), and the foil 3 can be placed in the recess 4.

[0071] According to FIG. 3D, the winding 8 is wound around the coil winding type 1, thereby forming a winding 9. The foil 3 selectively increases the diameter D of the winding 9 as schematically shown herein. The diameter of the component 7 is changed, in particular in the range of μm, according to the thickness of the foil 3. The winding 8 in this case is substantially longer than the foil 3. The winding 8 has at least one more turn than the foil 3. For example, the number of turns of the winding 8 is at least one-third greater than the number of turns k of the foil 3. This allows a large degree of freedom for adjusting the inductance.

[0072] According to FIG. 3E, the measured value M of the inductance is determined after the construction of the winding 9. If the inductance is close enough to the target value, the length l of the foil 3 is defined for a group of components. If the target value has not yet been reached, the length l of the foil 3 is further changed based on the measured value M.

[0073] By adjusting the number of turns of the foil 3, a very precise adjustment of the inductance of the component 7 can be achieved. For example, depending on the design, the inductance can be adjusted very precisely in steps of 0.1% within a range of up to 10%. The target value of the inductance is, for example, 1 to 1000 nH.

Explanation of Signs

[0074] 1 Coil winding type 2 Base body 3 Foil 4 Concave portion 5 Restriction portion 6 Restriction portion 7 Inductive component 8 Winding 9 Winding 10 End of the winding 11 End of the winding b Width of the concave portion B Width of the winding k Number of turns of the foil n Number of turns of the concave portion m Number of turns of the winding D Diameter of the winding M Measured value

Claims

1. An inductive component, which is a coil-wound type and is configured as a carrier for a winding (8) and includes a base body (2), a coil-wound type (1); an electrical insulation foil (3), wherein a partial region of the base body (2) is wound with the electrical insulation foil (3); a winding (9) formed by a winding (8) wound around the coil-wound type (1), whereby the electrical insulation foil (3) is disposed between the radially outward winding (8) and the base body (2), and including the winding (9); the electrical insulation foil (3) extends over at most two-thirds of the possible maximum effective axial length of the electrical insulation foil (3), whereby the electrical insulation foil (3) will be present below the axial length of the entire winding (9), whereby, along the axial length of the winding, in some regions, the winding (8) is disposed outside the electrical insulation foil (3), and in some regions, the winding is disposed directly on the base body (2), and the diameter of the winding (9) is increased in the region along the axial length of the winding where the winding is disposed outside the electrical insulation foil (3), the inductive component.

2. The inductive component according to claim 1, wherein the base body (2) is made of a non-magnetic material.

3. The inductive component according to any one of claims 1 to 2, wherein the electrical insulation foil (3) is made of a non-magnetic material.

4. The inductive component according to any one of claims 1 to 3, wherein the electrical insulation foil (3) has a maximum thickness of 100 μm.

5. The inductive component according to any one of claims 1 to 4, wherein the coil-wound type (1) includes a recess (4), and the electrical insulation foil (3) is disposed within the recess (4).

6. The inductive component according to claim 5, wherein the recess (4) is helical and includes at least two turns.

7. The inductive component according to claim 5 or 6, wherein the winding (8) is arranged in the recess (4).

8. The inductive component according to any one of claims 1 to 7, wherein the electrical insulating foil (3) is wound helically around the base body (2), and the number of turns (k) of the electrical insulating foil (3) is at most two-thirds of the number of turns (m) of the winding (8).

9. A method for setting the inductance value of a group of inductive components of the same design, wherein at least a part of the region of the base body (2) of the coil winding type (1) is wound with an electrical insulating foil (3), the axial length of the electrical insulating foil (3) is selected according to the target value of the inductance, and then the coil winding type (1) is wound with a winding (8), whereby the electrical insulating foil (3) is arranged in at least a part of the region between the winding (8) in the radial direction and the base body (2), the winding (8) is arranged outside the electrical insulating foil (3) in some regions along the axial length of the wound winding, and is also arranged directly on the base body (2) in some regions, the inductance of the inductive component (7) is measured after being wound with the winding (8), and, If the target value has not yet been reached, the length of the electrical insulating foil (3) for a further inductive component (7) of the same design is changed from the target value according to the deviation of the measured value. When the measured inductance is smaller than the desired target value, an electrical insulating foil (3) having a length longer than that of the measured inductive component is selected for the further inductive component (7), or when the measured inductance is larger than the desired target value, an electrical insulating foil (3) having a length shorter than that of the measured inductive component is selected, Otherwise, when the target value is reached, the length of the electrical insulating foil (3) is defined for the group of inductive components.

10. The method according to claim 9, wherein the electrical insulation foil (3) is wound helically around the base body, and the length (l) of the electrical insulation foil (3) varies in steps smaller than one turn of the electrical insulation foil (3) around the coil winding type (1).

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