Coil of a loudspeaker

Abstract

This invention relates to a loudspeaker coil, preferably for a planar loudspeaker. The coil includes at least one winding (10) extending around a coil core (12), wherein the winding (10) has a connection area (16) for fixing to the loudspeaker on the side opposite to the coil core (12). The coil winding of the loudspeaker of this invention is composed of anodized aluminum strip. Because the anodized layer is extremely thin compared to other insulation methods and the conductor cross-section is rectangular, an extremely high fill factor can be achieved. There are no air gaps between the windings, thus the magnetic field can be fully utilized.

Description

Technical Field

[0001] This utility model relates to the field of electrical technology, specifically to a loudspeaker coil, preferably used in a planar loudspeaker. Background Technology

[0002] German patent document DE 10 2018 124 261 A1 discloses a planar loudspeaker comprising a planar acoustic plate and a drive unit for driving the acoustic plate. The drive unit includes a plate-shaped coil carrier having a coil formed thereon and a magnet assembly. The coil carrier is arranged in the gap between two magnet units of the magnet assembly.

[0003] However, structures using coil carriers have the disadvantage of high cost of magnet components. In addition, the manufacturing process is complex and inefficient.

[0004] Therefore, the purpose of this invention is to provide a speaker coil and a speaker containing the coil, thereby reducing costs and improving efficiency. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a loudspeaker coil that solves the problems of high cost and low efficiency of magnet components in existing coil-carrier structures.

[0006] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0007] One aspect provides a speaker coil, preferably for a planar speaker, comprising at least one winding extending around a coil core, characterized in that: the winding has a connection area for fixing to the speaker on the outer side opposite to the coil core.

[0008] Preferably, the winding is formed in a strip-like structure.

[0009] Preferably, the width of the winding is at least five times its height.

[0010] Preferably, the winding comprises or is made of aluminum and / or copper.

[0011] Preferably, the winding has an insulating layer, preferably an anodized layer and / or an insulating varnish layer.

[0012] Preferably, multiple overlapping windings are provided.

[0013] Preferably, the end of the innermost winding or the conductor electrically connected to it is led out from the inside across all windings to the outside.

[0014] Preferably, the coil core comprises air and / or plastic material, preferably fiber-reinforced plastic, or is composed of such material.

[0015] On the other hand, a loudspeaker, preferably a planar loudspeaker, is provided, which includes at least one of the coils described above.

[0016] Preferably, at least one magnet is provided, the magnetic field of which acts on the coil, wherein the dot product of the normal vector of the coil surface and the magnetic flux density inside the coil is positive in one part of the coil and negative in another part.

[0017] By employing the above technical solution, this utility model provides a speaker coil, which has at least the following beneficial effects:

[0018] The speaker coil provided by this utility model does not have a coil carrier. The coil without a carrier structure can significantly reduce costs. The winding is composed of anodized aluminum strip. Since the anodized layer is extremely thin compared to other insulation methods and the conductor cross-section is rectangular, an extremely high fill factor can be achieved. There are no air gaps between the windings, so the magnetic field can be fully utilized, improving efficiency. Attached Figure Description

[0019] The accompanying drawings, which are included to provide a further understanding of the present invention, form part of this application:

[0020] Figure 1 This is a perspective view of the speaker coil of this utility model;

[0021] Figure 2 for Figure 1 The diagram shows a 3D view of the coil in its installed state.

[0022] Figure label:

[0023] 10 - Winding; 12 - Coil core; 14 - End; 16 - Connection area; 18 - Diaphragm; 20 - Support. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] This embodiment provides a loudspeaker coil, preferably for a planar loudspeaker, i.e., a planar loudspeaker. The coil includes at least one winding (10) extending around a coil core (12), and the coil (10) has a connection area (16) for fixing to the loudspeaker on the side opposite to the coil core (12). Preferably, the coil is fixed to the loudspeaker only through this connection area (16), so the winding can be directly fixed to the loudspeaker, for example, fixed to the diaphragm (18) and / or the centering device or the support (20) of the centering device, for example, by adhesive bonding.

[0026] The speaker's coil does not have a coil carrier. A carrier-free coil can significantly reduce costs. For example, compared to the same coil with a 1 mm thick coil carrier, a carrier-free structure can reduce magnet costs by about 20%.

[0027] In another embodiment, the winding (10) is formed in a strip structure, for example, the winding may have a rectangular cross-section, which is particularly helpful in achieving a high fill factor, for example, about 95%.

[0028] In another embodiment, the width of the winding (10) is at least five times its height, for example, the width may be between 1 mm and 10 mm, such as 4 mm, while the height may be between 0.05 mm and 0.5 mm, such as 0.15 mm.

[0029] In another embodiment, the winding (10) comprises or is composed of aluminum and / or copper materials, preferably aluminum strip, or copper wire.

[0030] According to a further embodiment, the winding (10) includes an insulating layer, preferably an anodic oxide layer and / or an insulating varnish layer, and preferably, the winding (10) is composed of anodized aluminum strip. The thickness of the anodic oxide layer can be, for example, between 1 μm and 10 μm, for example, about 4 μm. The anodic oxide layer is used to electrically insulate the overlapping windings. Because the anodic oxide layer is extremely thin compared to other insulation methods and the conductor cross-section is rectangular, a very high fill factor can be achieved, for example, about 95%. There are no air gaps between the windings, so the magnetic field can be fully utilized. This high fill factor allows the coil to obtain the maximum driving force per unit magnet volume, thereby minimizing the cost of the required magnet.

[0031] Furthermore, using a low-mass aluminum coil, whose resistance is comparable to that of a copper coil, can significantly improve efficiency, as the coil accounts for approximately 80% to 90% of the total mass of moving parts in a coil loudspeaker. Since the extremely small air volume in the loudspeaker acts as a spring, a large-size and high-power strong drive coil is required to achieve low-frequency reproduction. Alternatively, the winding can be made of copper wire with an adhesive varnish layer (i.e., an orthogonal winding coil).

[0032] According to another embodiment, a plurality of overlapping windings (10) are provided. Preferably, the windings are integral structures, i.e., multiple windings are formed by winding a strip multiple times. Since the coil is formed by winding only a single strip and / or has only a single-layer winding structure, its manufacturing process is simplified and the cost is lower compared with other types of coils.

[0033] Furthermore, a winding is considered as a complete turn of the coil core (12). Preferably, only the innermost winding is in contact with the coil core (12). Overall, the windings can be arranged in an elliptical shape, or at least substantially rectangular. The rectangular shape can have rounded corners, which can be rounded to semicircular. Preferably, the height of all windings is greater than their width. The overlapping windings (10) can be connected to each other, preferably by adhesive bonding. For example, epoxy resin can be used as the adhesive material. Preferably, the epoxy resin is applied after the windings are completed. The adhesive material can be, for example, an adhesive, potting material, and / or plastic, which serves to bond and fix the windings together. The adhesive material is distributed almost only in the gaps between the windings. The windings can also be selectively or additionally fixed by pressure. For example, the windings can be permanently compressed using a device acting on the outermost winding.

[0034] According to another embodiment, the end (14) of the innermost winding (10), or the conductor electrically connected thereto, extends from the inside across all windings (10) to the outside. For this purpose, the end may be folded at least once or twice. The electrical conductor may be made of, for example, aluminum (such as anodized aluminum) and / or copper. The conductor may be connected to the end by welding, brazing, bonding, and / or crimping.

[0035] Preferably, the end or electrical conductor rests against the winding surface but is electrically insulated from the winding by an insulating layer (e.g., polyimide tape), and an electrical connection terminal can be connected to the end or electrical conductor leading to the outside.

[0036] The end of the innermost winding, i.e. the starting part of the strip, and / or the end of the outermost winding, i.e. the end of the strip, preferably do not have an insulation layer. For example, the insulation layer can be removed and a metal plate, such as a copper plate, can be connected by welding. Flexible metal strands (such as copper strands) can be welded to the metal plate by soft soldering, or the metal strands can be directly connected to the strip by welding and / or soft soldering.

[0037] According to a further embodiment, the coil core (12) comprises air and / or plastic material, preferably fiber-reinforced plastic, or is composed of such material; when the coil core is air, there is actually no solid coil core. In this case, a high-strength adhesive material can be used to ensure that the coil maintains its predetermined shape.

[0038] The invention also relates to a loudspeaker, preferably a planar loudspeaker, which includes at least one coil as described above.

[0039] According to one embodiment, at least one magnet is provided, whose magnetic field acts on the coil. The magnet may have different magnetization directions or polarities in different regions. Alternatively, at least two magnets with different magnetization directions or polarities may be provided. In one section of the coil, the dot product of the normal vector of the coil surface and the magnetic flux density is positive, while in another section it is negative. The short side of the coil (e.g., a rectangular coil) or the vertex (e.g., an elliptical coil) is preferably arranged parallel to the direction of movement of the coil.

[0040] Figure 1 A loudspeaker coil, preferably a planar loudspeaker coil, is shown, comprising multiple windings (10). The windings (10) are overlapped. However, only a single layer of windings is provided, i.e., all windings are located in the same plane. The windings (10) extend around a coil core (12). The end (14) of the innermost winding (10) extends from the inside across all windings (10) to the outside. The windings (10) have a connection area (16) for fixing to the loudspeaker on the side opposite to the coil core (12).

[0041] like Figure 2 As shown, the coil is fixed to the diaphragm (18) and the support member (20) of the centering device via the connecting area (16), for example by adhesive bonding.

[0042] It should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0043] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A coil of a loudspeaker for a planar loudspeaker comprising at least one winding (10) extending around a coil core (12), characterized in that: The winding (10) has a connection area (16) on the outer side opposite to the coil core (12) for fixing to the speaker.

2. The coil of claim 1, wherein: The winding (10) is formed in a strip structure.

3. The coil according to claim 1, characterized in that: The width of the winding (10) is at least five times its height.

4. The coil according to any one of claims 1 to 3, characterized in that: The winding (10) comprises or is made of aluminum and / or copper.

5. The coil according to any one of claims 1 to 3, characterized in that: The winding (10) has an insulating layer, which is an anodic oxide layer and / or an insulating varnish layer.

6. The coil according to any one of claims 1 to 3, characterized in that: Multiple overlapping windings (10) are provided.

7. The coil according to claim 6, characterized in that: The end (14) of the innermost winding (10) or the conductor electrically connected to it is led out from the inside across all windings (10) to the outside.

8. The coil according to any one of claims 1 to 3, characterized in that: The coil core (12) comprises air and / or plastic material, which is fiber-reinforced plastic, or is composed of such material.

9. A loudspeaker, a planar loudspeaker, characterized in that: It includes at least one coil according to any one of claims 1 to 8.

10. The loudspeaker according to claim 9, characterized in that: At least one magnet is provided, whose magnetic field acts on the coil, wherein the dot product of the normal vector of the coil surface and the magnetic flux density inside the coil is positive in one part of the coil and negative in another part.

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