Coil for a loudspeaker

Abstract

Coil for a loudspeaker, preferably planar loudspeaker, comprising at least one turn (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 area (16) for fastening to the loudspeaker.

Description

The invention relates to a coil for a loudspeaker, preferably planar loudspeakers.DE 10 2018 124 261 A1 discloses a planar loudspeaker which comprises a planar 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 magnetic device. The coil carrier is arranged in a gap between two magnet units of the magnet device.However, a bobbin has a disadvantage that the cost of the magnetic device is comparatively high.It is therefore an object of the invention to provide a coil for a loudspeaker and a loudspeaker in which / the costs are low.This object is achieved by the subject matters of the independent claims.According to the invention, the coil is suitable for a loudspeaker or can be used for this purpose.The loudspeaker can preferably be a planar loudspeaker, that is to say a flat loudspeaker.The coil has at least one winding, wherein the winding extends around a coil core.An outer side of the winding opposite the coil core has a fastening region for fastening to the loudspeaker. Preferably, the coil is fastened to the loudspeaker exclusively via this fastening region.The winding is thus fastened, for example glued, directly to the loudspeaker, for example a membrane and / or a centring device or a holder of the centring device.A coil carrier is not provided here.The unsupported coil results in the costs being able to be reduced.For example, an identical coil with a 1 mm thin coil carrier would result in approximately 20% increased magnetic costs.Further developments of the invention can also be taken from the dependent claims, the description and the accompanying drawings.According to one embodiment, the winding is configured in the form of a band.For example, the winding can have a rectangular cross-sectional area.The rectangular conductor cross section contributes in particular to the fact that a good fill factor, for example of approximately 95%, is present.According to a further embodiment, the width of the winding is at least five times greater than the height of the winding.For example, the width may be between 1 mm and 10 mm, e.g. 4 mm, and the height may be between 0.05 and 0.5 mm, e.g. 0.15 mm.According to a further embodiment, the winding comprises or consists of an aluminum material and / or a copper material.Preferably, an aluminium strip is provided.Alternatively, a copper wire is also conceivable, for example.According to a further embodiment, the winding comprises an insulation layer, preferably an efloxacin layer and / or an adhesive lacquer layer.Preferably, the winding is made of an anodized aluminum strip. The efloxacin layer can have a thickness of between 1 μm and 10 μm, for example 4 μm, for example. The eloxat layer electrically isolates turns lying one above the other from one another.The extremely thin eloxat layer and the rectangular conductor cross section in comparison with other insulation possibilities result in an extraordinarily good fill factor of, for example, approximately 95%.No air is present between the windings, so that the magnetic field is utilized well.The fill factor maximizes the force that the coil can reach per magnet volume, thus minimizing the cost of the magnets needed. In addition, an aluminum coil having a low mass achieves an electrical resistance comparable to a copper coil.Since the coil makes up about 80% to 90% of the moving mass in a loudspeaker, this greatly increases the efficiency. Due to the tiny volume of air, which behaves like a spring in the loudspeaker, extremely strong drives with large, powerful coils are required for low-frequency reproduction.The winding may alternatively consist of a copper wire with an adhesive lacquer layer (ortho-cyclic coil).According to a further embodiment, a plurality of turns wound one above the other are provided.The windings are preferably integral, i.e. for example a band can be wound several times and in this way form several windings.Because the coil consists only of a single wound strip and / or has only one winding layer, the production outlay and thus the costs are low compared to other coils.A complete winding around the coil core is considered as a winding.Preferably, only the innermost winding lies against the coil core.Overall, the windings can be arranged, for example, in the manner of an ellipse or at least substantially in the shape of a rectangle.The rectangular basic shape can have, for example, rounded corners, wherein the corners can be rounded up to the semi-circular shape.Preferably, the height of all the turns is greater than the width of the turns.The windings lying one above the other can be connected, preferably glued, to one another, for example. For example, an epoxy resin may be used as the bonding agent. Preferably, the epoxy resin is applied after winding the windings.The connecting means, which can be, for example, an adhesive, a potting compound and / or a plastic, connects the windings to one another. In this case, the connecting means is located almost exclusively between the windings.The windings can alternatively or additionally be pressed together. For example, the coils may be permanently compressed over the outermost coil by a device.According to a further embodiment, an end region of the innermost winding or an electrical conductor connected thereto is led from the inside outwards over all windings.For this purpose, the end region can be folded at least once or twice, for example.The electrical conductor can comprise or consist of, for example, an, for example anodized, aluminum material and / or copper material. The conductor can be soldered, welded, glued and / or pressed to the end region, for example.The end region or the electrical conductor preferably abuts the windings. However, this is electrically separated from the windings by an insulating layer, for example a polyimide tape.An electrical connection can be fastened to the end region or electrical conductor that is led to the outside.The end region of the innermost winding, i.e. quasi the tape start, and / or the end region of the outermost winding, i.e. quasi the tape end, can preferably be free of an insulation layer. For example, the insulation layer can be removed and a metal plate, e.g. a copper plate, can be fastened, e.g. welded on. A flexible metal strand, e.g. copper strand, can be soldered onto the metal lamina, for example by means of a soft solder. Alternatively, the metal strand can also be welded and / or soldered directly to the strip, for example by means of a soft solder.According to a further embodiment, the coil core comprises or consists of air and / or a, preferably glass fiber-reinforced, plastic material.In the case of a coil core made of air, therefore, no coil core at all is provided to some extent. In this case, a strong connecting means can be helpful, for example, which ensures that the coil remains in the desired shape.Finally, the invention relates to a loudspeaker, preferably planar loudspeaker, having at least one coil according to the invention.According to one embodiment, at least one magnet is provided, the magnetic field of which acts on the coil.The magnet can have a different magnetization or polarity in sections, for example. Alternatively, at least two differently magnetized or poled magnets can also be provided.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.The short sides of the (e.g. rectangular) coil or the vertices of the (e.g. ellipsoidal) coil can preferably be oriented parallel to the direction of movement of the coil.All aspects, embodiments and features of the invention described here can be combined with one another, preferably also separately from the specific configuration in the context of which they are mentioned. Preferably, all the subjects of the dependent claims can be combined with each other and with each subject of the independent claims.The invention is described below by way of example with reference to the drawings. The following are shown: FIG. 1 is a perspective view of an embodiment of a coil according to the invention; and FIG. 2 is a perspective view of the coil according to FIG. 1 in the installed state.First, it should be noted that the illustrated embodiments are merely exemplary in nature. Thus, individual features can be realized not only in the combination shown, but also alone or in other technically meaningful combinations. For example, the features of one embodiment can be combined with features of another embodiment as desired. Preferably, the number and / or shape of the windings may 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.If a figure contains a reference sign which is not explained in the directly associated text of the description, reference is made to the corresponding preceding or following explanations in the description of the figures. Thus, the same reference numerals are used for identical or comparable components in the figures and these are not explained again.FIG. 1 shows a coil for a loudspeaker, preferably planar loudspeaker, having a plurality of windings 10.The windings 10 are wound one above the other. However, only one winding layer is provided, i.e. the windings lie in the same plane.The windings 10 extend around a coil core 12.An end region 14 of the innermost winding 10 is led from the inside outwards over all windings 10.An outer side of the windings 10 opposite the coil core 12 has fastening regions 16 for fastening to the loudspeaker.As can be seen in FIG. 2, the coil is fastened, for example glued, to a membrane 18 and to a holder 20 of a centering device via the fastening regions 16.List of reference characters10 Winding 12 Coil core 14 End region 16 Fastening region 18 Diaphragm 20 HolderReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedDE 10 2018 124 261 A1

[0002]

Claims

Coil for a loudspeaker, preferably 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 the coil core (12) has a fastening region (16) for fastening to the loudspeaker.Coil according to claim 1, characterised in that the winding (10) is of strip-shaped design.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).Coil according to one of the preceding claims, characterized in that the winding (10) comprises or consists of an aluminium material and / or a copper material.Coil according to one of the preceding claims, characterized in that the winding (10) comprises an insulation layer, preferably an efloxacin layer and / or an adhesive lacquer layer.Coil according to one of the preceding claims, characterized in that a plurality of turns (10) wound one above the other are provided.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 outwards from the inside over all the windings (10).Coil according to one of the preceding claims, characterized in that the coil core (12) comprises or consists of air and / or a, preferably glass fibre-reinforced, plastic material.Loudspeaker, preferably planar loudspeaker, comprising at least one coil according to one of the preceding claims.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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