Coil for a loudspeaker

Abstract

The invention relates to a coil for a loudspeaker, preferably a planar loudspeaker, having at least one winding (10), wherein the winding (10) extends around a coil core (12), and wherein an outer side of the winding (10) opposite to the coil core (12) has an attachment region (16) for attachment to the loudspeaker.

Description

[0001] Coil for a loudspeaker

[0002] The invention relates to a coil for a loudspeaker, preferably a planar loudspeaker.

[0003] DE 10 2018 124 261 A1 discloses a planar loudspeaker comprising a flat sound panel and a drive unit for driving the sound panel. The drive unit has a plate-shaped coil carrier with a coil formed thereon and a magnet device. The coil carrier is arranged in a gap between two magnet units of the magnet device.

[0004] However, a coil carrier has the disadvantage that the costs for the magnetic device are comparatively high.

[0005] It is therefore an object of the invention to provide a coil for a loudspeaker and a loudspeaker which are low in cost.

[0006] This problem is solved by the subject matter of the independent claims.

[0007] According to the invention, the coil is suitable for a loudspeaker or can be used for this purpose.

[0008] The loudspeaker can preferably be a planar loudspeaker, i.e. a flat loudspeaker.

[0009] The coil has at least one turn, wherein the turn extends around a coil core.

[0010] An outer side of the winding, opposite the coil core, has a mounting area for attachment to the loudspeaker. The coil is preferably attached to the loudspeaker exclusively via this mounting area.

[0011] The winding is thus attached, e.g. glued, directly to the loudspeaker, e.g. a membrane and / or a centering device or a holder of the centering device.

[0012] A coil carrier is not provided here.

[0013] The carrier-free coil means that costs can be reduced.

[0014] For example, an identical coil with a 1 mm thin coil carrier would result in approximately 20% increased magnet costs.

[0015] Further developments of the invention can also be found in the dependent claims, the description and the accompanying drawings.

[0016] According to one embodiment, the winding is band-shaped.

[0017] For example, the winding may have a rectangular cross-sectional area.

[0018] The rectangular conductor cross-section contributes in particular to a good fill factor, e.g. of about 95%.

[0019] According to a further embodiment, the width of the winding is at least five times greater than the height of the winding.

[0020] For example, the width can be between 1 mm and 10 mm, e.g. 4 mm, and the height between 0.05 and 0.5 mm, e.g. 0.15 mm.

[0021] According to a further embodiment, the winding comprises or consists of an aluminum material and / or a copper material. Preferably, an aluminum strip is provided.

[0022] Alternatively, a copper wire is also conceivable.

[0023] According to a further embodiment, the winding comprises an insulating layer, preferably an anodized layer and / or an adhesive lacquer layer.

[0024] The winding is preferably made of an anodized aluminum strip. The anodized layer can have a thickness between 1 pm and 10 pm, e.g., 4 pm. The anodized layer electrically insulates overlapping windings from one another.

[0025] The extremely thin anodized layer and the rectangular conductor cross-section, compared to other insulation options, achieve an exceptionally good fill factor of approximately 95%.

[0026] There is no air between the windings, so the magnetic field is used effectively.

[0027] The fill factor maximizes the force the coil can achieve per magnet volume, thus minimizing the cost of the required magnets. Additionally, with a low-mass aluminum coil, an electrical resistance comparable to that of a copper coil is achieved.

[0028] Since the coil accounts for approximately 80% to 90% of the moving mass in a loudspeaker, this increases efficiency enormously. Due to the tiny air volume, which acts like a spring in the loudspeaker, extremely powerful drives with large, high-performance coils are required for bass reproduction.

[0029] Alternatively, the winding can consist of a copper wire with an adhesive coating (orthocyclic coil). According to another embodiment, several windings wound one above the other are provided.

[0030] The windings are preferably one piece, ie for example a band can be wound several times and in this way form several windings.

[0031] Because the coil consists of only a single wound strip and / or has only one layer of winding, the manufacturing effort and thus the costs are low compared to other coils.

[0032] A turn is considered to be a complete winding around the coil core.

[0033] Preferably, only the innermost winding rests on the coil core.

[0034] Overall, the windings can be arranged, for example, in an elliptical or at least essentially rectangular manner.

[0035] The rectangular basic shape can, for example, have rounded corners, whereby the corners can be rounded up to a semicircle shape.

[0036] Preferably, the height of all turns is greater than the width of the turns.

[0037] The superimposed turns can be connected to each other, preferably glued. For example, an epoxy resin can be used as a bonding agent. The epoxy resin is preferably applied after the turns have been wound.

[0038] The connecting material, which can be an adhesive, a potting compound, and / or a plastic, connects the windings together. The connecting material is located almost exclusively between the windings.

[0039] Alternatively or additionally, the coils can be crimped. For example, the coils can be permanently pressed together by a device across the outermost coil.

[0040] According to a further embodiment, an end region of the innermost winding or an electrical conductor connected thereto is led from the inside over all the windings to the outside.

[0041] For this purpose, the end area can be folded at least once or twice.

[0042] The electrical conductor may, for example, comprise or consist of an anodized aluminum and / or copper material. The conductor may be soldered, welded, glued, and / or crimped to the end portion, for example.

[0043] Although the end portion or the electrical conductor is preferably in contact with the windings, it is electrically separated from the windings by an insulating layer, e.g., a polyimide tape.

[0044] An electrical connection can be attached to the end section or electrical conductor that leads to the outside.

[0045] The end region of the innermost turn, i.e., the beginning of the strip, and / or the end region of the outermost turn, i.e., the end of the strip, can preferably be free of an insulating layer. For example, the insulating layer can be removed and a metal plate, e.g., a copper plate, can be attached, e.g., welded on. A flexible metal strand, e.g., a copper strand, can be soldered to the metal plate, for example, using a soft solder. Alternatively, the metal strand can also be welded and / or soldered directly to the strip, e.g., using a soft solder.

[0046] According to a further embodiment, the coil core comprises or consists of air and / or a plastic material, preferably glass fiber reinforced.

[0047] With a coil core made of air, there's essentially no coil core at all. In this case, a strong connecting element can be helpful, for example, to ensure the coil retains its desired shape.

[0048] Finally, the invention relates to a loudspeaker, preferably a planar loudspeaker, with at least one coil according to the invention.

[0049] According to one embodiment, at least one magnet is provided, the magnetic field of which acts on the coil.

[0050] The magnet can, for example, have different magnetization or polarity in certain sections. Alternatively, at least two differently magnetized or polarized magnets can be provided.

[0051] The scalar product of a normal vector of a coil surface and a magnetic flux density in the coil is positive in one section of the coil and negative in another section of the coil.

[0052] The short sides of the (e.g. rectangular) coil or the vertices of the (e.g. elliptical) coil can preferably be oriented parallel to the direction of movement of the coil.

[0053] All aspects, embodiments, and features of the invention described here can be combined with each other, preferably independently of the specific embodiment in which they are mentioned. Preferably, all subject matter of the dependent claims can be combined with each other and with each subject matter of the independent claims.

[0054] The invention is described below by way of example with reference to the drawings.

[0055] Fig. 1 is a perspective view of an embodiment of a coil according to the invention, and

[0056] Fig. 2 is a perspective view of the coil according to Fig. 1 in the installed state.

[0057] First, it should be noted that the illustrated embodiments are purely exemplary in nature. Individual features can be implemented not only in the combination shown, but also individually or in other technically feasible combinations. For example, the features of one embodiment can be combined arbitrarily with features of another embodiment. Preferably, the number and / or shape of the windings can vary. Furthermore, the shape and / or configuration of the coil core can vary. For example, it can be completely filled with air or completely filled with a solid material.

[0058] If a figure contains a reference symbol that is not explained in the immediately corresponding description, reference is made to the corresponding preceding or following explanations in the figure description. Thus, the same reference symbols are used for identical or comparable components in the figures and these are not explained again.

[0059] Fig. 1 shows a coil for a loudspeaker, preferably a planar loudspeaker, comprising several windings 10. The windings 10 are wound one above the other. However, only one winding layer is provided, ie, the windings lie in the same plane.

[0060] The windings 10 extend around a coil core 12.

[0061] An end region 14 of the innermost winding 10 is led from the inside over all windings 10 to the outside.

[0062] An outer side of the windings 10 opposite the coil core 12 has fastening areas 16 for fastening to the loudspeaker.

[0063] As can be seen in Fig. 2, the coil is attached, e.g. glued, to a membrane 18 and to a holder 20 of a centering device via the attachment areas 16.

[0064] List of reference symbols

[0065] 10 turns

[0066] 12 Coil core 14 End area

[0067] 16 Mounting area

[0068] 18 Membran

[0069] 20 bracket

Claims

Claims 1 . Coil for a loudspeaker, preferably a planar loudspeaker, comprising at least one winding (10), wherein the winding (10) extends around a coil core (12), and wherein an outer side of the winding (10) opposite the coil core (12) has a fastening region (16) for fastening to the loudspeaker.

2. Coil according to claim 1, characterized in that the winding (10) is band-shaped.

3. Coil according to claim 1 or 2, characterized in that the width of the winding (10) is at least five times greater than the height of the winding (10).

4. Coil according to one of the preceding claims, characterized in that the winding (10) comprises or consists of an aluminum material and / or a copper material.

5. Coil according to one of the preceding claims, characterized in that the winding (10) comprises an insulating layer, preferably an anodized layer and / or an adhesive lacquer layer.

6. Coil according to one of the preceding claims, characterized in that several windings (10) wound one above the other are provided.

7. Coil according to claim 6, characterized in that an end region (14) of the innermost winding (10) or an electrical conductor connected thereto is led from the inside over all the windings (10) to the outside.

8. Coil according to one of the preceding claims, characterized in that the coil core (12) comprises or consists of air and / or a plastic material, preferably reinforced with glass fiber.

9. Loudspeaker, preferably planar loudspeaker, with at least one coil according to one of the preceding claims.

10. Loudspeaker according to claim 9, characterized in that at least one magnet is provided, the magnetic field of which acts on the coil, the scalar product of a normal vector of a coil surface and a magnetic flux density in the coil being positive in one section of the coil and negative in another section of the coil.

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