Planar dynamic acoustic transducer

Abstract

The present invention relates to a planar dynamic acoustic transducer (0) having at least one magnet device (1) having a plurality of magnetic poles and at least one acoustic aperture (13), and a diaphragm (2) having at least one conductor track (21), wherein the magnet device (1) has an inner region (11) containing magnetic poles and a peripheral region (14) surrounding the inner region (11) and connecting its elements to each other, and the inner region (11) of the magnet device (1) is vertically offset relative to the horizontal (X, Y) from the conductor track (21) of the diaphragm (2) and is arranged to at least overlap, preferably coincide, with the conductor track (21) of the diaphragm (2) in the horizontal (X, Y). The planar dynamic acoustic transducer (0) is characterized in that the peripheral region (14) of the magnet device (1) further comprises at least one mechanical, acoustic and / or electrical function of the planar dynamic acoustic transducer (0).

Description

Technical Field

[0001] The present invention relates to a planar dynamic acoustic transducer.

Background Art

[0002] For example, in order to generate sound in a loudspeaker, a so-called acoustic transducer that converts a voltage into an acoustic signal is used as a sound source. Conversely, an acoustic transducer can also convert an acoustic signal as an alternating sound pressure into an electrical signal or voltage converted by, for example, a microphone. This can be done according to different principles.

[0003] 1. Dynamic Acoustic Transducer Today, electrodynamic or dynamic loudspeakers operating according to electrodynamic principles are widely used. Therefore, a conductor is placed in a magnetic field. A magnetic field can be generated using either a magnetic field coil or a permanent magnet. When the conductor is energized here, due to the Lorentz force depending on the direction of the current, mechanical movement of the conductor occurs. The mechanical movement of the conductor is usually transmitted to the air as the surrounding medium with the help of a diaphragm element, where it causes sound waves as an acoustic signal. Detection of the acoustic wave can be reversed and used, for example, in a microphone.

[0004] Dynamic acoustic transducers with a conical shape design are widely used, which consist of a magnet system, also known as a magnetic device, a voice coil, a formed diaphragm, a suspension, and a housing or chassis. Depending on how the magnetic field is generated, it can be called an electrodynamic conical loudspeaker or a permanent magnet conical loudspeaker. In any case, the conical design of the diaphragm and the cylindrical shape of the voice coil result in a relatively high structure in the sound emission direction, thus resulting in a relatively large installation space. The components of such a dynamic acoustic transducer also bring a non-negligible weight. Sound waves are generated in small areas or specific points that do not correspond to natural sound waves. Furthermore, the strict mechanical tolerances required between the coil and the magnet system, as well as the complex assembly of the above-mentioned parts and other individual parts, result in significant development and manufacturing costs.

[0005] Nevertheless, acoustic transducers based on the above-established dynamic acoustic transducer principle are dominant in commercial products, but dynamic acoustic transducers have drawbacks regarding output and sound quality, which can only be alleviated with great effort.

[0006] For example, the diaphragm can be designed flat. However, in this design, the tendency to unwanted natural vibrations or modes increases, and it also has to be mechanically damped and stiffened, which increases the moving mass and impairs the reproduction of high acoustic frequencies with high inertia. For example, simplifying the magnet system by omitting the pole plates or positioning the voice coil lower within the magnet system results in a less convergent, non-uniform magnetic field that is asymmetric with respect to the rest position of the diaphragm, which leads to a decrease in efficiency as well as an increase in non-linearity and acoustic distortion. Approaches that generate the driving force radially with respect to the diaphragm axis and mechanically redirect it axially (see, for example, WO 2011 / 013223 (A1)) result in a significantly more complex design combined with a significantly increased cost for the structural parts and their assemblies.

[0007] U.S. Patent Application Publication No. 2015 / 256912 (A1) shows an example of a dynamic loudspeaker having a flat diaphragm integrated with a larger structure. The trim part of the automobile interior has an aperture, and a flat loudspeaker diaphragm composed of a circumferential elastic surround and a rigid diaphragm panel is inserted into this aperture. A bridge-shaped support is attached to the back of the trim part, and this support spans across the diaphragm opening, and an electromagnetic actuator is attached to the center, and its voice coil deflects the diaphragm from its rest position to generate sound. There has been some progress in terms of the depth of the overall structure and the complexity of the assembly. However, the drawbacks of the flat diaphragm design already described also exist here, and a number of individual components are still required, which have to be pre-manufactured separately and then assembled.

[0008] 2. Electrostatic acoustic transducer Another known principle of an acoustic transducer is the electrostatic system, which consists of one or two flat electrode grids and a flat stretched membrane film arranged between them. A relatively high polarization voltage modulated by an effective signal generates an electrostatic force between the diaphragm and the electrodes, and this electrostatic force deflects the diaphragm to generate sound.

[0009] The purpose of a flat design and a relatively simple structure related to many applications is achieved here. For this reason, the prior art includes, for example, the application of this principle for sound insulation in the interior of automobiles in German Patent Application Publication No. 102006045385 (A1). However, during operation, there is a risk that the diaphragm may come into contact with one of the electrodes due to excessive deflection or external air pressure fluctuations and adhere electrostatically until the polarization voltage is switched off.

[0010] To reduce this risk of interruption, other means such as additional electrical insulation, a multilayer diaphragm structure, or high mechanical diaphragm tension are required, increasing the manufacturing cost and impairing the acoustic output (decrease in efficiency, mass attenuation of high vibration frequencies, decrease in low-frequency reproduction due to high fundamental resonance frequencies). There are also drawbacks due to the polarization voltage, which is typically in the hundreds of volts. In case of malfunction, this can pose a danger or obstacle to people or technical systems. Furthermore, parasitic electrical effects in the supply lines depend on the length of the lines and result in significant voltage drops that have to be compensated for by technical effort, for example by a higher supply voltage or a complex line structure. Alternatively, a high-voltage source can be placed very close to the acoustic transducer, but this requires additional lines for the supply voltage and additional installation space. In applications such as automotive interiors, each of these variants has considerable drawbacks.

[0011] 3. Surface transducer Different approaches are taken with surface transducers, flexural wave transducers, and similar systems. Here, a flat solid is excited by one or more point actuators to produce vibrations or flexural waves, which in turn result in sound radiation.

[0012] The drawback here is that considerable design and signal processing means are required to achieve a sufficiently well-controlled acoustic behavior on the vibration surface. There must be no excessive or non-linear resonances at frequencies corresponding to the modes of the surface itself, and the output of the sound radiation should be as small as possible between these frequencies. This requirement is technically difficult, especially at high frequencies, because of the relatively large vibration mass.

[0013] Particularly efficient use of space is achieved as soon as existing surfaces from, for example, screens, furniture, or vehicle interior trim or body parts are used. Examples are US Patent No. 6,181,797 (B1) (automobile) and US Patent No. 6,332,029 (B1) (screens and other applications). However, this multiple use requires functional and design compromises. The shaping, assembly, thickness, and material composition, as well as the positioning of the actuator, can usually only be optimized for a very limited range of acoustic outputs, and the vibrations required can be harmful to the original function or lifespan of the flat structural parts. In addition, there are long-term signs of aging of the structural parts, which can significantly deteriorate their vibration characteristics, such as changes in elasticity (brittleness or softening), mechanical tolerances, or the bonding or connection to adjacent components.

[0014] 4. Planar dynamic principle Planar dynamic acoustic transducers have also been known for a long time, which consist essentially of one planar magnetic device or two planar magnetic devices, and a diaphragm provided with conductor tracks is arranged parallel to these planar magnetic devices or between these planar magnetic devices. When an electric current flows through the conductive conductor tracks, they interact with the magnetic field of the multipole magnet device to generate a force acting perpendicular to the diaphragm surface, elastically deflect the diaphragm, and generate air displacement and thus sound pressure.

[0015] This means that planar dynamic acoustic transducers can usually be configured thinner than dynamic acoustic transducers with a conical design, but planar dynamic acoustic transducers are longer and wider in the diaphragm plane. However, the increased radiation surface of planar dynamic acoustic transducers requires less excursion and thus less distortion. Furthermore, a relatively large area of acoustic radiation is achieved, which better corresponds to the conditions in a natural sound field than a more specific acoustic source with point contact represented by a dynamic acoustic transducer with a conical design. Another advantage of planar dynamic acoustic transducers is that the mass of the membrane film and planar conductor tracks is generally significantly smaller, which can improve the dispersion behavior of pulses, transient currents, and high-frequency components.

[0016] In other words, a planar dynamic acoustic transducer (which is also called an orthodynamic transducer or an isodynamic transducer) has a planar diaphragm on which conductor tracks are arranged. The planar diaphragm is parallel to a magnet device and has a short interval with respect to the magnet device. The magnet device generates a multipole magnetic field such that the magnetic field lines in the region of the conductor tracks extend tangentially to the diaphragm and perpendicular to the conductor tracks. When a current flows through the conductor tracks, a force acting perpendicular to the diaphragm is generated, deflecting the diaphragm to generate sound. Such an acoustic transducer can be used as an acoustic transducer in loudspeakers and headphones. In the reverse mode, that is, by deflecting the diaphragm by acoustic sound and thereby inducing an alternating current, it can also be used as a microphone.

[0017] A planar dynamic acoustic transducer generally consists of a plurality of structural components including magnetic rods or rings, brackets, reinforcing materials, adhesives, etc. These are manufactured individually and must be assembled. Conventional magnet devices for planar dynamic acoustic transducers use, for example, simple bar magnets having a north pole on one long side and a south pole on the opposite long side. These pre-magnetized rods must be arranged alternately and aligned in brackets and adhered to the brackets, which involves assembly work and material use. Other structural components such as spacer rings, contact parts, etc. are usually added.

[0018] In any case, next, the aforementioned assembly is assembled to form a planar dynamic acoustic transducer, and then the planar dynamic acoustic transducer is attached to final products such as loudspeakers, headphones, microphones, etc. In addition to brackets, frames, screw connections, and the like, acoustically effective structural components such as fabrics, resonators, foams, or so-called acoustic metamaterials are also used.

[0019] 5. Planar Dynamic Principle with Separate Magnets U.S. Patent Application Publication No. 5901235(A) describes a planar magnetic transducer having a diaphragm including a conductor attached to a frame, with spaced magnets arranged on both sides of the central sound generating surface region of the diaphragm by a metal support grid.

[0020] U.S. Patent No. 2015110339(A1) describes a planar multi - diaphragm electro - acoustic transducer in which a plurality of diaphragms are arranged within one or more diaphragm modules. Each diaphragm module includes at least one diaphragm, each of which is held taut by a frame.

[0021] U.S. Patent Application Publication No. 2018 / 0084346(A1) describes a planar speaker unit having a housing, a first magnet set, and a diaphragm. The housing has a receiving chamber and a bottom wall. The first magnet set is arranged on the bottom wall and located within the receiving chamber. The diaphragm is arranged within the receiving chamber and located above the first magnet set. The diaphragm includes a substrate and a planar coil. The planar coil is flatly attached on the substrate.

[0022] U.S. Patent No. 10003876(B2) describes a planar magnetic headphone consisting of a single layer of parallel, elongated magnets spaced apart and placed on a magnetic holder matrix. The holding matrix can be made of a plastic or metal - permeable plate, and the magnets are arranged inside the plate (towards the ear). Inside the magnets, a damping matrix made of plastic is provided, which supports a first continuous disc - shaped damping diaphragm. A serpentine conductor track is attached to a thin diaphragm arranged outside the magnets, which energizes the magnets to move the diaphragm and generate sound according to the current in the conductor track. Further, outside the conductor track, attached to the outer rigid plastic cover is a second continuous disc - shaped damping diaphragm.

[0023] German Patent Application Publication No. 102017102159 (A1) describes a planar dynamic acoustic transducer, which often consists of two opposing magnet devices each having a plurality of magnetic rods arranged in parallel, and a diaphragm having a flat coil therebetween. The plane of the magnet device is parallel to the diaphragm plane. The repulsive force between the two magnet devices and the connecting elements for fixing the device may cause stress, torsion, deflection, etc. Conventionally, the diaphragm film is directly fixed to the magnetic holder or fixed to a separate structural part, such as a carrier frame. The mechanical stress is transmitted to the very thin diaphragm film pre-stressed, impairing its flatness and / or the uniformity of the mechanical stress. In this planar dynamic transducer having a first planar magnet device, a fixing element, a diaphragm having conductor tracks, and at least one diaphragm support frame, the diaphragm support frame is clamped between the magnet device and the fixing element. An elastic separating element is arranged between the diaphragm carrier frame and the first magnet device and / or between the diaphragm carrier frame and the fixing element.

[0024] U.S. Patent Application Publication No. 2014 / 0270326 (A1) describes a planar magnetic transducer having a frame and a primary magnet row structure of elongated magnets adjacent to and having a gap from a first surface side of a movable portion of a thin film or thin-structured diaphragm, with conductor tracks incorporated in the diaphragm. An additional pair of magnetic sources are attached to the frame outside the vibratable region of the diaphragm and mounted on the plane of the second surface side opposite the diaphragm to amplify the magnetic energy near the second surface side of the foil diaphragm even without a row of magnets immediately in front of the vibratable region of the diaphragm between the additional pair of magnetic sources.

[0025] As is known from the relevant material data sheets, typically used magnetic rods made from neodymium (Nd2Fe14B), which are equally applicable to other designs such as rings, require a very high magnetic field strength H, for example 2400 kA / m, due to their high coercivity that is associated with the desired high energy density, in order to be fully magnetized or polarized up to the saturation range. Such a magnetic field strength can only be generated by a magnetization device (an electromagnet in the form of a solenoid or other shaped coil) with dimensions significantly exceeding those of the structural parts to be magnetized, even if such a magnetic field strength is only required in pulses.

[0026] Together with the requirement that the magnetic rods must be arranged with alternating polarities, this means that the magnetic rods must be magnetized individually before assembly. Thus, during assembly or positioning in an assembly device or injection molding tool, the magnetic rods are in a magnetized state and thus generate considerable mechanical repulsive or attractive forces depending on their relative positions to each other and to other ferromagnetic structural parts or tools. For example, the force between two magnetic rods made from a common neodymium alloy "N45" of 2×4×40 mm each is about 40 N upon contact and about 10 N at a distance of 2 mm.

[0027] To partially account for this problem, FIGS. 42 to 44 of U.S. Patent Application Publication No. 2005 / 036646 (A1) show a carrier grid having pins or webs protruding perpendicular to the surface, which pins or webs prevent the lateral movement of the magnetic bars due to repulsive / attractive forces until the adhesive between the magnetic bars and the carrier grid has cured. In particular, there is a certain attractive force between flat adjacent parallel magnetic rods, which usually have alternating polarities, and this must be counteracted in an appropriate way to maintain the desired position and spacing between the magnetic rods. However, when additional magnetic bars are added, they will lift or twist the already arranged bars from this position, or exert forces in different directions (especially if they are on a non-magnetic material) unless further measures are taken to temporarily fix them in place.

[0028] Another problem is the high brittleness and very low elasticity of the magnetic rods due to those powder metallurgy manufacturing methods. In the case of uncontrolled collisions or other increased forces, this often results in the breakage and fragmentation of the magnetic rods, leading to waste of materials and danger to people and equipment from flying debris or fragmentation. All the characteristics of the magnetic rods mentioned so far pose considerable effort in their storage, removal, handling, positioning, and temporary fixation until they are finally fixed in their final positions, for example, by clamping or bonding to carrier elements or by plastic overmolding.

[0029] Conventional planar dynamic acoustic transducers involve additional effort and cost due to their multi-component structure consisting of a carrier system for the magnetic rods, a carrier system for the diaphragm film, electrical connections, a mechanical interface to the housing and other structural parts, a protective grid, and a baffle or housing.

[0030] In International Publication No. WO 03 / 094571 (A2), FIGS. 15-27 to 15-29 and the related description describe an assembly method in which magnetic rods (15-2704, 15-2904) are placed in the cavities of an injection mold and fixed there by spring pins (15-2900). How these potentially conflicting steps (positioning, fixing, and subsequent closing of the injection mold) should be carried out is not described in detail, despite the detailed manufacturing process description elsewhere in International Publication No. WO 03 / 094571 (A2). The need for the fixing described here again shows the problem of the magnetic attraction force mentioned above.

[0031] Furthermore, the cavity wall, without going into further detail, can be made of ferromagnetic steel. The resulting attraction to the wall supports the temporary fixation of the magnetic rod, but at the same time, due to too fast an impact on the cavity wall, it poses a risk of material failure of the magnetic rod during insertion and also makes the demolding of the assembly much more difficult. The magnetic rod can be broken from the plastic if it adheres (magnetically) more strongly to the cavity wall or ejector than to the adjacent plastic parts.

[0032] In the next step, the magnetic rods of WO 03 / 094571 (A2) are joined to form an assembly by overmolding them with a suitable plastic that permanently fixes their relative positions and at the same time forms an acoustically open carrier grid (15 - 2600). The magnetic rods also have internal slots (15 - 2800), which are filled with plasticized plastic to achieve a secure fit. This also indicates that the material bond between the plastic and the usually smooth (e.g., nickel-plated) non-textured surface of the magnetic rod is insufficient and comparable to the desired low adhesion between the plastic and the cavity wall.

[0033] The additional mechanical processing steps required to form slots in brittle magnetic rods are generally very cost-intensive, partly due to the required slow processing speed and / or increased reject rate. The fact that the cost of mechanical processing of magnetic rods is very important is also shown by the description in WO 03 / 094571 (A2), according to which the alignment of the magnetic rods on the cavity wall shown in FIGS. 15 - 29 is advantageous because it can compensate for a larger thickness tolerance that can occur in order to save costs when manufacturing the magnetic rods.

[0034] 6. Planar dynamic principle using a magnetic disk For the purpose of simplifying the design and the required manufacturing process, planar dynamic acoustic transducers are known that use grids or perforated disks made of a continuous hard magnetic material. This results in investment costs for casting tools, but also simplifies assembly since there is only a single magnetic structural part, which is usually not yet magnetized and thus easy to handle. The relative and absolute positioning of the magnetic poles is usually guaranteed reproducibly in a subsequent magnetization process.

[0035] However, in the state of the art, this grid only has a magnetic function and thus always requires a separate carrier that provides mechanical coupling to other structural parts.

[0036] JP 2008113365 (A) shows such an acoustic transducer having perforated magnetic disks (22a, 22b) held by carrier grids (24a, 24b). Here, the acoustic transducer consists of seven structural parts and components for electrical and mechanical contact.

[0037] US 3674946 (A) describes a planar dynamic acoustic transducer that uses an elastic, pre-manufactured, multi-pole magnetized flat magnetic material ("Plastiform", for example type 1037), which is perforated by punching and similar methods and cut to a predetermined size. This is a barium ferrite bonded to rubber having a low energy product of only about 1.1 MGOe. This relatively weak magnetic material was chosen because, for example, due to the magnetic attraction between the magnetic material and the carrier grid, it is very easy to process, attach, and conform to the shape of a non-flat carrier grid. However, the magnetic field thus provided to drive the acoustic transducer is considerably weaker than the magnetic fields of other materials available at the time of filing of US 3674946 (A) and again considerably weaker than the magnetic field of today's neodymium magnets having an energy product of up to 52 MGOe. Due to the high elasticity of the magnetic material, the use of a support structure and other assembly components is essential.

[0038] In a later application (U.S. Patent No. 4,471,173(A)) by the same inventor, in addition to the elastic magnetic material described above, a more magnetically strong material made from rare earths such as samarium-cobalt, and the manufacture of a perforated magnetic disk by unspecified shaping (“shaped into the illustrated shape”) or punching (“die cut”) are described. This magnetic disk is an alternative to the single magnetic strip used in other embodiments of U.S. Patent No. 4,471,173(A), and thus also requires a separate carrier grid and other individual structural parts.

[0039] A further variant of the acoustically open magnetic disk is described in U.S. Patent No. 10,455,343(B2). The magnetic disk 14 shown therein is integrally manufactured and has solely a magnetic function, being supplemented by a carrier grid 16, a diaphragm carrier ring 12, and other structural parts. The magnetic disk 14 can be made from “any ferromagnetic material”, but the required or preferred energy product specification of 34 - 45 MGOe restricts the choice of material to anisotropic fully metallic rare earth magnets, in particular sintered neodymium magnets (Nd2Fe14B) commercially available in material grades having an energy product of 30 - 52 MGOe. The low geometric complexity of the magnetic disk enabling the manufacture of the magnetic disk by mechanical processing of the sintered neodymium material, as well as the uniform surface normal magnetization shown in FIGS. 1A and 4B, also indicate this anisotropic material. Alternative magnetic materials such as ferrite, AlNiCo, plastic-bonded neodymium (usually isotropic), and sintered samarium cobalt only achieve a maximum of 5, 9, 12, or 33 MGOe and are thus not very suitable for the acoustic transducer according to U.S. Patent No. 10,455,343(B2).

[0040] U.S. Patent Application Publication No. 3898598(A) describes a dynamic electroacoustic transducer that includes two slotted disks of permanent magnets spaced apart parallel to each other and generates a plurality of aligned magnetic fields of alternating polarities within the gap therebetween. A main diaphragm having a flat coil is kept flat by two auxiliary diaphragms sandwiching it, is disposed parallel to the disks within the gap, and the magnetic fields intersect perpendicularly with different portions of the coil. Two ring-shaped elastic holders clamp the peripheries of the main diaphragm and the auxiliary diaphragms between them to give the main diaphragm the required rigidity. Alternatively, a clamping ring can provide the required rigidity to the main diaphragm attached to a ring-shaped elastic holder.

[0041] Japanese Patent Application Laid-Open No. 2010-268045(A) relates to the problem of providing a thin electroacoustic transducer that can be assembled more easily than conventional ones and has an improved design. For this purpose, a planar loudspeaker used as a thin electroacoustic transducer has been proposed. It includes a pair of covers as a housing, and within this housing, four pins or the like are provided. The pins are held with both ends fitted into fitting holes provided in a permanent magnet plate, function as a positioning tool for positioning a vibration diaphragm and a corresponding buffer element when assembling the planar speaker, and function as a displacement control means for controlling the displacement direction of the vibration diaphragm after assembly. Further, the pins are incorporated into the housing to maintain the design including the flatness of the housing.

[0042] However, such planar dynamic acoustic transducers still consist of additional structural parts such as contact clamps, diaphragm rings, spacer rings, screw connections, etc., and have the drawback of causing corresponding manufacturing labor, tolerance chains, and costs.

[0043] For example, German Patent Application Publication No. 102017122660 (A1) describes a planar dynamic acoustic transducer including a magnetic plate having an elongated gap crossing a conductor. The magnetic plate is magnetized on one side with a plurality of poles such that each gap facing the diaphragm and the conductor includes at least one north pole and one south pole on both sides along the gap. This generates the strongest deflection force on the diaphragm directly below the magnetic rod and also the strongest acoustic attenuation. Since the width of the gap in the magnetic plate also does not depend on the width or spacing of the conductor tracks, it can be freely selected.

[0044] Nevertheless, the usually numerous individual components and assembly steps of a planar dynamic acoustic transducer result in various problems harmful to repairability and reusability, including corresponding manufacturing and assembly labor, various materials involving frequent use of adhesives, and quality issues due to the tolerance chain of the individual components stacked on top of each other. This results in a significant material cost and labor cost in the manufacture of this type of transducer, which is an obstacle to mass rational production and low unit price.

Prior Art Documents

Patent Documents

[0045]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

[0046] One object of the present invention is to provide a planar dynamic acoustic transducer of the above - described type that can simplify its manufacturing, particularly its assembly. Additionally or alternatively, the acoustic characteristics and / or electrical characteristics should be improved. This should be as simple, cost - effective, space - saving, and / or weight - saving as possible. At least, the object is to provide an alternative to known planar dynamic acoustic transducers.

Means for Solving the Problem

[0047] According to the present invention, this object is achieved by a planar dynamic acoustic transducer, a magnet device, a receiver, a microphone, and a loudspeaker having the features of the independent claims. Advantageous further developments are described in the dependent claims.

[0048] Thus, the present invention is a planar dynamic acoustic transducer having at least one magnet device having a plurality of magnetic poles and at least one acoustic aperture, and a diaphragm having at least one conductor track, wherein the magnet device has an inner region including magnetic poles and an edge region surrounding the inner region and connecting elements of the inner region to each other, and the inner region of the magnet device is horizontally and vertically offset from the conductor track of the diaphragm and is arranged to overlap at least horizontally with the conductor track of the diaphragm. A planar dynamic acoustic transducer of this type is known, for example, from US Patent Application Publication No. 3674946(A) described at the beginning.

[0049] The planar dynamic acoustic transducer according to the present invention is characterized in that the edge region of the magnet device further includes at least one mechanical, acoustic and / or electrical function of the planar dynamic acoustic transducer. The mechanical function can be understood to mean a mechanical connection, in particular a bracket or attachment, which may be direct or indirect, between the edge region of the magnet device and, in particular, the diaphragm. The mechanical function may be a vertical spacing, contact or non-spacing with respect to the horizontal plane between the edge region of the magnet device and the diaphragm. The acoustic function can be understood to affect acoustic sound generation or sound detection. The electrical function can be understood to be, in particular, the electrical contact of the conductor track of the diaphragm. Further mechanical, acoustic and / or electrical functions of the planar dynamic acoustic transducer enabled by the edge region of the magnet device are not excluded hereby.

[0050] In any case, the mechanical, acoustic and / or electrical properties of the planar dynamic acoustic transducer can thereby be improved or enhanced, either individually or in combination with each other, thereby correspondingly improving the quality of the planar dynamic acoustic transducer and corresponding products, such as earphones, particularly headphones, microphones, loudspeakers and the like. In addition or alternatively thereto, the manufacturing and especially the assembly effort can be reduced by taking over more functions from one structural component in the form of a magnet arrangement or its edge region or the same functions from fewer structural components, thereby saving additional structural components that would be required for manufacturing and assembly. In addition or alternatively thereto, certain design options, for example, as will be explained in more detail below, first make it possible to electrically contact the delicate conductor tracks of the diaphragm using the magnet arrangement.

[0051] In any case, the edge region of the magnet arrangement can not only serve to connect or mechanically hold together its elements such as the inner region or its magnetic poles, as has been known previously, but according to the invention, the edge region of the magnet arrangement can be made particularly large enough, especially in the radial or horizontal direction, in order to enable further mechanical, acoustic and / or electrical functions and properties as described above. The edge region of the magnet arrangement can be designed specifically such that the corresponding functions are possible and can be carried out as effectively as possible, in particular.

[0052] Preferably, the efficiency of the interaction between the magnetic poles of the magnet arrangement and the conductor tracks of the diaphragm can be increased by arranging the inner region of the magnet arrangement perpendicular to the horizontal plane with respect to the conductor tracks of the diaphragm and within the horizontal line that coincides with the conductor tracks of the diaphragm. In particular, the acoustic aperture of the magnet arrangement can extend in coincidence with the conductor tracks of the diaphragm.

[0053] According to one aspect of the present invention, the inner region of the magnet device and the edge region of the magnet device are integrally formed by the magnet body. At least the inner region of the magnet device contains a hard magnetic material and is preferably made of a hard magnetic material. The hard magnetic material is a permanent magnetic material and thus has a certain magnetic field and maintains it permanently. An alloy made of iron, cobalt, nickel, or a specific ferrite, or rare earths can be used to form the hard magnetic inner region of the magnet body and thus the magnetic poles of the magnet device.

[0054] In other words, according to the present invention, it is possible to omit additional magnetic elements as separate structural parts that are pre-applied to a grid or the like in order to form a known magnet device together with the grid. Rather, according to the present invention, the magnet device or its magnet body can be designed both as a mechanically stable element, in particular with an edge region having additional mechanical, acoustic and / or electrical functions as described above, and as a permanent magnet element in order to combine these properties, thus avoiding at least two structural parts in this respect for a planar dynamic acoustic transducer. Therefore, the installation can be simplified. This can also save weight and / or installation space, especially in a direction perpendicular to the horizontal plane.

[0055] This can be achieved by having the inner region of at least the magnet device have a hard magnetic material to a sufficient extent to achieve the desired interaction with the conductor track, and further by having an additional, preferably non-magnetic material to complete the magnet device or its inner region and form the edge region of the magnet device. Thereby, when the hard magnetic material is more expensive than the additional material, the manufacturing cost of the magnet device can be kept low. However, alternatively, the magnet device or its magnet body can consist entirely of a hard magnetic material at least in the inner region, which can simplify the manufacturing and, if necessary, make it more cost-effective. This can preferably also be applied to the edge region.

[0056] In any case, the magnet device can be formed in one piece, i.e., integrally or monolithically, which can be done by milling, compression molding, or stamping, but can also be done by primary molding such as injection molding, die casting, metal powder injection molding, 3D printing, etc. This can also make the manufacturing more cost-effective, especially when only one material is used. However, as described above, it is also possible to perform integral manufacturing using at least two different materials in a two-component process, for example by injection molding, so that at least two different materials can be combined and used with each other. For example, the inner region may partially or completely have a hard magnetic material or may consist of a hard magnetic material, while the edge region may consist of a non-magnetic material, which can save hard magnetic material and thus keep the manufacturing cost of the magnet device low.

[0057] It is particularly preferred that at least the inner region of the magnet device, particularly precisely or only the inner region of the magnet device, is made hard magnetic, and it is preferred to use hard magnetic particles such as neodymium-iron-boron embedded in a plastic material such as polyamide, particularly polyamide 6 or 12. For example, by a two-component injection molding method, by precisely placing or concentrating the hard magnetic particles only in the inner region of the magnet device, it is possible to use such hard magnetic particles precisely in the places where a magnetic field is required in order to keep the amount and thus the cost of the hard magnetic material as low as possible or to minimize it. In this case, the edge region of the magnet device may, in particular, not contain a hard magnetic material in order to save the cost of the hard magnetic material there.

[0058] According to a further aspect of the invention, the edge region of the magnet device is formed from a material different from the inner region of the magnet device, preferably from a material having a lower specific gravity, and / or from a material having a lower magnetization or no magnetization, and / or from an elastic material. Thereby, the related aspects above and below can be specifically implemented.

[0059] According to a further aspect of the invention, the internal region of the magnet device is formed from a first material in a first method step, and the edge region of the magnet device is formed from a second different material in a second method step. This can be carried out, for example, as a two-component injection molding method (2K injection molding). The names of the first and second materials should not be understood in the order of use.

[0060] For example, in a first partial step of the overall injection molding process, the structural grid is formed from a non-magnetic or weakly magnetic material component, which corresponds to the mechanical loads expected due to its shape and material properties (for example, added short glass or carbon fibers) and has the desired acoustic properties (for example, permeability or acoustic resistance).

[0061] After the grid has solidified sufficiently, a sub-element of the injection mold is moved in a second partial step, as a result of which a new cavity is formed in the internal region, which cavity corresponds approximately to the grid structure in the horizontal plane and is located on the side facing the diaphragm of the previously manufactured grid. Here, this new cavity can be filled with a magnetic material component, as a result of which the magnetic material component forms a relatively thin layer on the previously manufactured grid and bonds to the grid by plasticizing its surface.

[0062] In this way, the thickness, and thus the amount of magnetic material components required, is also reduced to a minimum necessary for magnetic field generation. Since the strength of the magnetizing magnetic field decreases exponentially with the distance to the flat magnetizing device in the case of one-sided multipole magnetization, for example, a material thickness of 30% of the pole spacing is sufficient for this purpose. For a pole distance of 5 mm (between the center lines of adjacent north and south pole strips), the thickness of the magnetic material components can thus be 1.5 mm. Edge regions and other related elements (such as walls for forming acoustic channels or speaker housings) that must meet lower mechanical requirements and are manufactured as part of the same overall injection molding process can be manufactured together with the structural grid from the same non-magnetic or weakly magnetic material components in a first partial step, or they can be manufactured in a third partial step from a third material component consisting only of, for example, a polymer matrix without a mixture.

[0063] In the third or fourth partial step, after the movement of the individual tool elements, partial regions made of an elastic material, for example, a circumferential seal ring or elements for vibration isolation, can be added, and an interlock connection between the elastic material and the adjacent already manufactured partial regions is achieved by appropriate material selection or material pairing and appropriate process parameters.

[0064] If possible surrounding or adjacent structural parts such as housing parts or linings are not manufactured in one of the above partial steps, they can also consist of fiber composites, press fiber materials, foamed plastics or metals, or similar materials, and they are inserted into the corresponding tool cavities and completely or partially penetrated by the melt mass introduced in another partial step, or bonded to it at the boundary regions by surface plasticization.

[0065] The selection and order of the partial steps described can be adapted to specific designs, material selections, and other requirements without departing from the basic concept of the present invention.

[0066] All of the above-described shapes of the magnet grid according to the present invention can be manufactured using other manufacturing methods, in particular additive manufacturing methods such as 3D printing, laser sintering, stereolithography, etc., or powder metallurgy methods such as laser melting, metal powder injection molding, etc., without departing from the basic concept of the present invention. Other structural parts such as the housing rear wall (which forms a hollow body and thus cannot be manufactured as a whole in an injection molding process) can be manufactured in the same printing process. Similarly, the acoustic transducer according to the present invention can be assembled or integrated into larger assemblies, structures, devices, housings, vehicles, etc. without departing from the basic concept of the present invention, using all conventional methods of joining techniques such as screw connections, snap fits, welding, soldering, adhesives, shrink fits, and overmolding and equivalent processes.

[0067] According to a further aspect of the present invention, an edge region, preferably a part of the inner region, of the magnet device is formed from a first material in a first method step, and then the remaining inner region of the magnet device, preferably, is formed from a second different material in a second method step. Preferably, in the first method step, an edge region and preferably a part of the inner region, in particular a web, of the magnet device is formed from a first material that is less magnetic or non-magnetic and mechanically relatively rigid and / or strong as an extension into the inner side of the edge region, and in a further method step, a further part of the inner region of the magnet device, in particular a web, is formed from a second material having hard magnetic properties. This can be an alternative option for mounting.

[0068] According to a further aspect of the present invention, the edge region comprises at least partially an elastic material. Preferably, the edge region is partially formed from a third different elastic material in a third method step. Preferably, in a further, preferably third method step, the edge region of the magnet device is complemented by one or more partial regions of an elastic material. This enables the edge region to be at least partially elastic or partially elastic. This can be done by using the corresponding material as part of a multi-step manufacturing method, in particular an injection molding method.

[0069] According to another aspect of the present invention, the edge region of the magnet device is formed higher perpendicular to the horizontal plane than the inner region of the magnet device. This means that the diaphragm can directly abut against the edge region of the magnet device perpendicular to the horizontal direction and be connected to the edge region by adhesion, ultrasonic welding, clamping, or other joining methods. In this way, the vertical distance with respect to the horizontal plane between the magnetic pole in the inner region of the magnet device and the conductor track of the diaphragm is necessary or normal for the vibration ability of the diaphragm and thus for sound generation, and can be created by the edge region of the magnet device itself. Therefore, additional structural parts as housing elements or support elements are not required, and the manufacturing effort can be reduced. This was previously an additional element or structural part that functioned as a support element, housing element, or carrier element for supporting, housing, or carrying the diaphragm or diaphragm film, for example, by adhesion, and its function can be additionally taken over by the raised edge region of the magnet device according to the present invention. So far, this may be an element or structural part that forms a vertical distance with respect to the horizontal plane between the magnet device and the diaphragm as a "loose" element without connection or adhesion, and as a result, its function may be further taken over by the raised edge region of the magnet device according to the present invention.

[0070] When the diaphragm is arranged perpendicular to the horizontal plane between the magnet device and the protective grid, a spacer element can be arranged between the diaphragm and the protective grid as a separate element, component, or structural part to achieve a corresponding distance for the vibration deflection of the diaphragm. However, alternatively, the edge region of the protective grid can be raised towards the diaphragm perpendicular to the horizontal plane as described above with respect to the edge region of the magnet device to achieve the necessary distance without an additional spacer element as a separate element, component, or structural part.

[0071] According to a further aspect of the invention, the conductor track of the diaphragm is conductively connected to the contact element of the edge region of the magnet device at at least one conductor track end, preferably at both conductor track ends. The magnet device, preferably the edge region of the magnet device, preferably in both cases, has an outer contact element designed to be conductively contacted, preferably soldered, from the outside of the magnet device. In this way, electrical contact with the usually very delicate diaphragm or its conductor track can be made by means of the corresponding conductive contacts of the magnet device, which itself is usually much larger and more stable than the diaphragm. This enables, on the one hand, a relatively thin or delicate design of the diaphragm and, on the other hand, electrical contact of the conductor track of the diaphragm, for example by means of relatively solid electrical contact elements and in particular solder joints. For this purpose, the magnet device can be used for an electrical bridge between the conductor track of the diaphragm and a connecting element or solder joint that can be electrically contacted from the outside of the planar dynamic acoustic transducer. The conductive connection between the end of the conductor track or between both ends of the conductor track can in particular be made via a contact surface, and if necessary, an additional conductive adhesive can be provided at this point.

[0072] According to another aspect of the invention, the planar dynamic acoustic transducer has at least one support element, which is arranged perpendicular to the horizontal plane between the edge region of the magnet device and the diaphragm and separates the inner region of the magnet device from the diaphragm by means of a hollow inner region. Alternatively, this can be used to create the necessary or normal distance perpendicular to the horizontal plane between the magnetic poles of the inner region of the magnet device and the conductor track of the diaphragm, for which purpose additional structural parts are required as support elements or housing elements, but the design of the magnet device can be simplified.

[0073] According to a further aspect of the invention, the conductor track of the diaphragm is conductively connected to the contact element of the support element at at least one conductor track end, preferably at both conductor track ends, and the support element preferably in each case has an outer contact element which is designed to be conductively contacted, preferably soldered, from the outside of the magnet device. In this way, in order to achieve the necessary distance perpendicular to the horizontal plane between the magnetic pole of the magnet device and the conductor track of the diaphragm, if the support element is provided perpendicular to the horizontal plane without the magnet device being raised at the edge, the above-described characteristics and advantages can alternatively be achieved. This can also, in this case, enable the implementation of the above-described manner of electrical contact, and the electrical contact can be made from the outside of the planar dynamic acoustic transducer on the support element.

[0074] According to another aspect of the invention, the acoustic aperture of the magnet device at least substantially, preferably completely, follows the path of the conductor track of the diaphragm. In other words, the acoustic aperture of the magnet device and the conductor track of the diaphragm at least substantially, preferably completely, overlap when viewed in a direction perpendicular to the horizontal plane. In this way, unequal magnetic poles are provided parallel to each conductor track portion on both sides thereof. The magnetic field lines passing between these magnetic poles are optimally aligned tangentially to the conductor track by this arrangement and have a substantially constant density over the entire length of the conductor track. Thereby, the magnetic material used can be optimally utilized, and a driving force that is particularly uniformly distributed over the diaphragm surface can be achieved.

[0075] According to a further aspect of the invention, the acoustic aperture and the conductor tracks of the diaphragm of the magnet device are substantially elongated and extend parallel to each other in the direction of the maximum extent of the magnet device. For this purpose, at least the acoustic aperture and the conductor tracks of the diaphragm of the magnet device can be rectangular or oval with a horizontally elongated extension. The rectangular or oval design represents a preferred or maximum expansion and thus also a preferred option for the overall shape of the magnet device and thus also for the entire planar dynamic acoustic transducer. In any case, the number of parallel conductor track segments and connection pieces (sweeping parts) can be minimized, thereby simplifying the manufacture of the magnet device. This can also reduce the number of parts of the conductor tracks that contribute relatively little to the drive of the planar dynamic acoustic transducer near the edge region of the magnet device. However, since the current during operation, and thus the driving force, can decrease with the length of the conductor track and thus with the increase in the value of the electrical resistance of the conductor track, the length of the conductor track, and thus also its electrical resistance, is increased.

[0076] According to a further aspect of the invention, the edge region of the magnet device has at least one guide groove, preferably a pair of guide grooves, a diaphragm, preferably a support element and / or a spacer element and / or a protective grid, and at least one through-opening, preferably a pair of through-openings, for the guide grooves of the magnet device. This also enables the edge region of the magnet device to perform an additional mechanical function, facilitates assembly by means of the guide grooves, improves the fitting or alignment of the magnet device and the diaphragm, and in some cases other elements or components of the planar dynamic acoustic transducer, and arranges the diaphragm and in some cases other elements, components, or structural parts on the guide grooves and can thus be guided and arranged in a defined manner with respect to the magnet device. This can be achieved in particular by a pair of guide grooves. However, more than two guide grooves may also be used, which can improve the guidance accordingly, despite the increased effort.

[0077] Preferably, the ends of the guide slots can be formed by applying force and / or heat after the assembly of the diaphragm and / or other structural components in order to fix the diaphragm and / or other structural components. This can ensure permanent retention while being easy and inexpensive for feedthrough. This can be done more effectively the more guide slots are used, while the number of guide slots should be appropriately limited to minimize labor. For example, the use of 4 to 8 guide slots can represent a compromise between labor and effectiveness.

[0078] In any case, when using a plurality of guide slots, it is advantageous to distribute the guide slots as evenly as possible in the circumferential direction of the planar dynamic acoustic transducer. This can serve both for guidance and support.

[0079] Alternatively, when the diaphragm is arranged perpendicular to the horizontal plane between the magnet device and the protective grid, this can also be implemented such that one or more guide slots are arranged at the edge of the protective grid, in particular integrally formed there, and the edge region of the magnet device has one or more corresponding through openings. In this way, the same effect can be achieved using the same technical means, and it is only necessary to arrange them differently with respect to the magnet device and the protective grid.

[0080] According to a further aspect of the invention, the edge region of the magnet device has at least one receiving part, preferably a plurality of receiving parts, for accommodating fixing means, preferably screws, and the diaphragm, preferably the support element and / or the spacer element and / or the protective grid has at least one through-opening, preferably a plurality of through-openings, for the fixing means. This enables a mechanically simple and durable connection. In particular, screws can be used for this purpose, and the screws can be removed particularly easily and non-destructively for replacing elements, or for repairing the planar dynamic acoustic transducer, or for separating its individual parts and feeding them into the material cycle (recycling). For this purpose, such receiving parts can also be formed as female threads or can be provided with threaded inserts.

[0081] According to a further aspect of the invention, the edge region of the magnet device has at least one snap hook, preferably a plurality of snap hooks, for gripping around the diaphragm, preferably the spacer element or the protective grid, and preferably the snap hook head facing away from the magnet device is magnetically formed. In other words, this can be used to provide a catch, latch, or clamp connection for holding and positioning elements or structural components of the planar dynamic acoustic transducer, and can alternatively be implemented simply and inexpensively. In particular, this enables the holding function to be combined with the positioning function in one element or one step, which can be particularly simple and cost-effective.

[0082] Preferably, the snap hook can be magnetically designed at its upper end, particularly perpendicular to the horizontal plane, for magnetically attaching other structural components such as the ear pads of the headphones thereto. This can enable additional functions in a simple, cost-effective, and / or space-saving manner.

[0083] According to a further aspect of the invention, the edge region has at least one, preferably horizontal, cavity, preferably a plurality of, preferably horizontal, cavities, the cavities preferably opening into at least one acoustic aperture, particularly preferably a plurality of acoustic apertures, and the length of the cavity and / or the distance between two apertures of the cavity being selected such that at least one acoustic frequency at which the wavelength is in a predetermined ratio to the length of the cavity and / or the distance between two apertures of the cavity undergoes resonance and / or reflection.

[0084] According to a further aspect of the invention, the inner region, preferably at least one magnetic web of the inner region, more preferably a plurality of magnetic webs, most preferably all magnetic webs, have at least one, preferably horizontal, cavity, preferably a plurality of, preferably horizontal, cavities, the cavities preferably opening into at least one acoustic aperture, more preferably a plurality of acoustic apertures, and the length of the cavity and / or the distance between two apertures of the cavity being selected such that at least one acoustic frequency at which the wavelength is in a predetermined ratio to the length of the cavity and / or the distance between two apertures of the cavity undergoes resonance and / or reflection.

[0085] Thus, the cavities can be introduced into the inner region and / or the edge region of the magnet arrangement, preferably horizontally and / or parallel to the maximum extent of the magnet arrangement, for example by means of a slider in an injection moulding tool, by mechanical post-treatment or by means of a corresponding additional primary shaping such as laser sintering, 3D printing. These cavities can be provided with apertures at selected positions through which the sound flow can enter and exit. At certain acoustic frequencies at which the wavelength is in a specific ratio to the cavity length or aperture distance, resonance and / or reflection can occur, and these can overlap with the regular acoustic radiation of the planar dynamic acoustic transducer. This superposition can be constructive or destructive depending on the phase position of the resonance and / or reflection. This means that the sound emitted externally can be amplified or attenuated at these frequencies.

[0086] This enables acoustically effective shaping of the magnet device. This can be done using only the edge region of the magnet device or only the inner region of the magnet device. However, for this purpose, both regions of the magnet device can also be used in combination with each other. In any case, the system can be designed for maximum absorption and destructive interference in order to minimize the sound emitted externally. Alternatively, this design can also be used, for example, to reduce unwanted reflections and standing waves from the rear housing wall in headphones having a closed housing. Alternatively, for example, high frequencies emitted by a diaphragm having a reduced sound pressure due to mass suppression can be amplified by the resonator effect and thus create a uniform and linear sound impression up to high frequencies.

[0087] According to a further aspect of the invention, the inner region is acoustically more transparent, particularly for particularly high acoustic frequencies, or else is not acoustically more transparent for particularly high acoustic frequencies. In other words, this provides shaping of the aperture region in a partial region of the inner region with acoustic transparency, also for particularly high acoustic frequencies, with respect to the structure of the inner region, while in the remaining region of the grid, the aperture region is shaped to be acoustically less transparent or non-transparent, particularly for particularly high acoustic frequencies. As a result, the size of the acoustic aperture becomes smaller, which leads to a reduction in the directivity of the acoustic radiation determined by the ratio between the size of the radiating surface and the signal frequency.

[0088] According to a further aspect of the invention, the planar dynamic acoustic transducer has a pair of mirror-symmetrical magnet devices that surround the diaphragm perpendicular to the horizontal plane. This enables the magnet devices to be arranged on both sides of the diaphragm and can expand the design possibilities of the planar dynamic acoustic transducer. By implementing this with two identical and mutually compatible mirror-symmetrical magnet devices, the same structural components can be used twice, thus keeping the manufacturing costs low.

[0089] In other words, both magnet devices can preferably be substantially identical and symmetrical along the main axis. Both magnet devices can preferably be mechanically reinforced by their shape and / or by embedding them in stiffening elements and / or by connecting them to stiffening elements.

[0090] According to a further aspect of the invention, the magnet device has magnetic poles and at least one further inner region surrounded by an edge region.

[0091] In other words, the edge region is shaped to have one or more additional inner regions of magnetic material and an optional accommodation for a diaphragm film with conductor tracks. These additional inner regions may be arranged adjacent to the first inner region or may completely or partially surround the first inner region. These inner regions can be made to operate as further independent acoustic transducers by attaching a diaphragm film with contacted conductor tracks. These can differ from each other and / or from the first acoustic transducer, for example, in size, grid structure, diaphragm displacement, etc., and are thus suitable, for example, for reproducing different frequency ranges. For this purpose, the various acoustic transducers can be excited with their own electrical signals containing only the relevant signal frequencies. These signals can be generated, for example, by digital signal processing and subsequent digital-to-analog conversion and amplification, or by passive structural components such as capacitors or passive filter networks.

[0092] The advantage is that the individual acoustic transducers can be dimensioned and optimized for the reproduction of their respective frequency ranges. For example, low signal frequencies usually require a fairly large diaphragm area and diaphragm stroke, while high signal frequencies can be emitted by a light diaphragm with a small surface area. This also prevents a strongly increasing directivity of the acoustic radiation towards higher frequencies.

[0093] Particularly small embodiments of the first or additional grid regions and associated diaphragms are also suitable for use as electrodynamic microphones.

[0094] The different acoustic transducers described above can also be shaped and excited in the same or identical manner using different digitally-analog converted and amplified signals generated, for example, by digital signal processing such as beamforming or wavefront synthesis, in order to obtain, for example, controllable directivity of acoustic radiation or simulation of an arbitrarily shaped acoustic wavefront. In this way, a localized sound or a virtual acoustic environment can be created.

[0095] According to a further aspect of the invention, the magnet device has no magnetic poles and has at least one further internal region surrounded by an edge region. The further internal region can also be referred to as the second internal region in order to distinguish it from the internal region previously considered alone as the first internal region.

[0096] In other words, the edge region is shaped to have one or more additional internal regions that do not have a magnetic material and have an optional receiving portion for the diaphragm film. These additional internal regions may be arranged adjacent to the first internal region or may completely or partially surround the first internal region. These internal regions can be made to operate as so-called passive radiators by attaching a diaphragm film. They can differ from each other and / or from the first acoustic transducer, for example, in terms of size, grid structure, diaphragm stroke, etc., and have corresponding primary resonance frequencies together with the combined air volume. To adjust this resonance frequency, for example, to obtain a desired low value, the pretension and mass of the diaphragm film can be varied, for example, by changing the film thickness, or by mechanically structuring (corrugating, embossing, etc.) the diaphragm film, or by using additional materials having a mass that is permanently bonded to the diaphragm film, for example, by adhesion, lamination, overmolding, etc. The passive radiator can be strongly acoustically coupled to the active acoustic transducer at the rear by a common volume of air separated from the surroundings, so that the passive radiator is excited to resonate by these at a specific signal frequency with a phase shift. As a result, additional acoustic radiation at a specific frequency is obtained, which is mainly superimposed on the acoustic radiation of the active acoustic transducer by design, and thus increases the total acoustic energy radiated in these frequencies, for example, in the bass range.

[0097] According to a further aspect of the invention, the edge region of the magnet device has at least one additional wall that extends substantially outside the horizontal line and acoustically separates the internal region of the magnet device from a further internal region. In particular, the additional second wall may extend substantially exactly perpendicular to the horizontal plane or may extend away from the edge region that may be considered to extend horizontally. In any case, the additional wall can provide structural and / or acoustic separation.

[0098] According to a further aspect of the invention, the edge region of the magnet device is formed as a baffle.

[0099] In other words, the edge region is shaped to perform the function of a baffle, i.e., to substantially prevent acoustic short - circuiting between the front and back of the diaphragm in the relevant frequency range, and thus to improve the reproduction of low audio frequencies (e.g., bass). For this purpose, the edge region can be enlarged to such an extent that a sufficiently long detour is created for the sound waves generated at the rear, so that at the desired acoustic reception position at the lowest relevant signal frequency, it only minimally and destructively overlaps with the sound waves generated at the front, i.e., the phase difference between these two sound waves is reduced from the original 180° to less than 140° (a maximum amplitude reduction of about 3 dB due to destructive interference). In the same manufacturing process, additional functional features such as recesses, holes, hooks, bolts, bars, etc. can be created, for example, for assembly with other structural parts and structures and separation from other structural parts and structures.

[0100] Alternatively, the edge region may be shaped to form the front wall and / or side wall of the speaker housing, and may have features such as holes, threads, snap - hooks, etc. for attaching one or more structural parts forming the side wall and / or rear wall. In this way, a completely or partially closed loudspeaker housing can be formed. This prevents or reduces acoustic short - circuiting even when the dimensions are significantly smaller than those required for the baffle described above.

[0101] For efficient and integrated manufacturing, the edge region extended to form the baffle or speaker housing part can also be incorporated into other structural parts such as a flat housing, a vehicle body, or a trim component such as a housing part of a screen or lighting fixture, the outer surface of furniture or a ceiling suspension device, or the interior trim of a vehicle, and can be manufactured wholly or partly together with the structural part in the same injection - molding process.

[0102] In addition, the edge region may have a further wall extending preferably substantially perpendicular to the diaphragm plane between the drive region and the outer edge of the edge region. These further walls can, in some cases together with a separate rear wall, form an acoustic channel of defined length, which guides acoustic energy from the rear of the membrane to an acoustic outlet located in one of the outer housing walls. Thus, depending on the length and cross-sectional area of the channel, an acoustic bypass similar to the acoustic bypass of the baffle described above is formed, but with dimensions significantly smaller than the dimensions required for the baffle described above.

[0103] Alternatively, a resonance system is formed by the air (moving mass) in the channel and the air (acoustic spring) outside the channel in the closed housing, causing an increase in acoustic radiation at the resonance frequency.

[0104] The shape and / or surface area of the acoustic channel may be constant or variable over its length and may be linear, curved or inclined. Thereby, for example, a horn, a reverse horn or a so-called transmission line is formed. These further walls can also divide the housing volume, in some cases together with a separate rear wall, to provide an independent air volume for each acoustic transducer, for example if one or more active acoustic transducers are present.

[0105] According to a further aspect of the invention, the edge region of the magnet device has at least one wall extending substantially outside the horizontal line, which wall at least partially surrounds at least one internal region. In other words, a part of the edge region of the magnet device may be formed as one or more walls extending substantially outside the horizontal line that at least partially or completely surround at least one internal region. Optionally, this wall can also be designed as the rear wall of the housing connected, for example, by a film hinge.

[0106] Thereby, a panel or wall can be formed as a lateral boundary, preferably integrally with the edge region, thereby increasing the design freedom. This can also increase the stability of the magnet device.

[0107] According to a further aspect of the present invention, the magnet device forms, together with the rear wall, the housing of the planar dynamic acoustic transducer. This can be used to create an encapsulated or enclosed space.

[0108] Preferably, the rear wall is connected, preferably by a film hinge and preferably integrally, to the wall of the edge region of the magnet device, which can simplify assembly and manufacturing.

[0109] According to a further aspect of the present invention, the edge region of the magnet device extends substantially outside the horizontal line and has at least one wall forming at least one acoustic channel, which acoustic channel is designed to be acoustically in communication with the air volume above the internal region and the ambient atmosphere. In other words, the edge region of the magnet device extends substantially outside the horizontal line and has one or more additional walls forming one or more acoustic channels, and the acoustic channels are acoustically in communication with the volume of air above the internal region, or the volume of air above one or more optional further internal regions and the ambient atmosphere. This can increase the design options.

[0110] According to a further aspect of the present invention, the edge region of the magnet device preferably extends substantially horizontally and has at least one surface element preferably formed integrally. In other words, the edge region of the magnet device can have one or more further surface elements, which can be used for assembly or integration into a larger assembly, device, or vehicle. This can facilitate the assembly of the planar dynamic acoustic transducer.

[0111] The present invention also relates to a magnet device for use in a planar dynamic acoustic transducer as described above. In this way, the magnet device can be made available as a structural part or assembly so as to implement the planar dynamic acoustic transducer according to the present invention as described above and utilize its characteristics and advantages.

[0112] The present invention also relates to an earphone, preferably a headphone, having at least one planar dynamic acoustic transducer as described above. In this way, the characteristics and advantages of the planar dynamic acoustic transducer according to the present invention described above can be implemented and utilized in an earphone, particularly a headphone.

[0113] The present invention also relates to a microphone having at least one planar dynamic acoustic transducer as described above. In this way, the characteristics and advantages of the planar dynamic acoustic transducer according to the present invention can be implemented and utilized in a microphone as described above.

[0114] The present invention also relates to a loudspeaker comprising at least one planar dynamic acoustic transducer as described above. In this way, the characteristics and advantages of the planar dynamic acoustic transducer according to the present invention can be implemented and utilized in a loudspeaker as described above.

[0115] The present invention relates to a loudspeaker-microphone combination having at least one planar dynamic acoustic transducer as described above, wherein at least an inner region having an associated first diaphragm is configured as a loudspeaker and at least a further inner region having an associated further diaphragm is configured as a microphone. This can be an advantageous way of implementing or utilizing corresponding characteristics and advantages.

[0116] In other words, the present invention relates to a magnet device, which can also be called a magnet grid or a magnet system. The magnet device can be manufactured (monolithically) integrally with a suitable sound passage aperture, for example, by milling, injection molding, die casting, metal powder injection molding, compression molding, 3D printing, etc., and can be made of a suitable material such as a plastic matrix (e.g., polyamide 6 or 12) that can be filled with hard magnetic particles such as neodymium iron boron at least or exactly in the internal region. The filling degree of the hard magnetic particles in the surrounding material can be made as high as possible for the high efficiency of the acoustic transducer, but can be adjusted according to the requirements of the part shape and the manufacturing process. When using anisotropic particles, an appropriate magnetic field can be applied during the primary forming process or in a downstream process to mechanically align the magnetic particles, for example, using a permanent magnet or an electromagnet in an injection mold.

[0117] Aspects of the present invention may in particular, in addition to or instead of each other, be the following.

[0118] A planar dynamic acoustic transducer comprising a multipole magnetization grid made of a material containing a hard magnetic material and substantially made of 1 to 4 individual parts, and a substantially planar diaphragm film in which conductor tracks are arranged substantially parallel and in direct proximity to the grid and which generate a substantially perpendicular region force when a current flows by interacting with the magnetic field of the grid, wherein the magnet grid has additional specific characteristics or configurations and / or elements and / or features beneficial to the output, quality and / or assembly of the acoustic transducer and / or the product in addition to providing the magnetic field directly required for acoustic generation.

[0119] The special feature of this aspect according to the present invention can be seen in the shaping and construction of the magnet grid for improving the characteristics and / or output as an acoustic transducer or for increasing the functionality in order to achieve higher benefits, better quality, and lower costs. Specific features will be described below.

[0120] The magnet device or magnet grid can have additional mechanical and / or magnetic features such as assembly holes, studs, recesses, snap hooks, spacer stages, carrier stages, magnetic poles outside the surface of the movable diaphragm, etc., which can enable the positioning, alignment, spacing, and / or attachment of additional components or elements such as diaphragm films, protective grids, acoustic damping materials, housings, ear pads, a second mirror magnet grid, etc.

[0121] Thus, as described above, the planar dynamic acoustic transducer and related products can have other structural parts in addition to the magnet grid, and these structural parts can be positioned and fixed relative to each other, or must be fixed. The magnet grid may have various elements or features that facilitate these purposes or replace some structural parts or accessories. This example is as follows. a. Guide grooves: These can be made of the same base material as the magnet grid and thus form a natural unit with the magnet grid, i.e., be integrated with each other or, during manufacturing, for example, by injection molding or 3D printing, place them in the mold as inserts approximately and inject the moldable magnetic material around them, thus firmly connecting to the magnet grid by forming a solid unit with it. One or more such studs can be used to enable "screwing" or positioning other structural parts using corresponding holes or recesses. Conversely, such studs can also be connected to another structural part and inserted into the corresponding holes of the magnet grid. Combinations are also possible, i.e., for example, the magnet grid can have guide grooves on one side and holes symmetrically on the opposite side. Next, a second similar magnet grid rotated 180° can be connected to the first magnet grid and aligned on both studs to obtain a symmetric drive system with two opposing magnet grids. b. Snap hooks: These can be barbs that are deflected slightly during assembly to snap back to their original shape behind the mating part, creating a positive fit that secures the structural component and requires no further working steps or aids such as adhesives, screws, rivets, etc. At the same time, the snap hooks can also have a guiding and aligning function, like the guide grooves below point a. When forming the magnet grid, the snap hooks and similar functions can be formed from the base material and form a natural unit with the magnet grid, or a separate hook made, for example, from spring steel can be used and connected (e.g., overmolded) to the magnet grid during the forming process. c. Distance and carrier stage: Some structural components, such as diaphragm films, can be positioned and fixed at a defined distance from the magnet grid. For this purpose, the magnet grid can have a circumferential step of appropriate height that creates this distance, which can also be the direct carrier of the diaphragm film by attaching it onto the circumferential step by means of adhesion, clamping, or other methods. Similar solutions can also be realized for other structural components such as protection grids, dust protection, seals, acoustic damping elements, etc. d. Holes: When various structural components are connected to each other or to a housing, etc. using screws, in a conventional design, a holding frame that holds the magnet device and has holes can be used. According to the present invention, the magnet grid can include these holes, which can be through-holes for screws or threaded holes for metric or tapping screws (optionally with threaded inserts or press-in nuts). This reduces or eliminates additional work, tolerance risks, and costs that may be associated with, for example, a conventional assembly of 10 magnetic rods and a holding frame. e. Additional poles: Due to the basic manufacturing method of the magnet grid, the hard magnetic material is also available outside the actual drive area (near the conductor tracks) and can be magnetized as required. These additional poles can be used to attract other permanent magnets or electromagnets or ferromagnetic structural parts and thus position and fix them in place. This example is a protective grid made from a steel or ear pad with an integrated carrier ring made of steel or individual magnets integrated therein. These structural parts can be removed and reattached without tools or auxiliary materials, which can be particularly advantageous for the end user. These poles do not have to be arranged at the height of the drive area, but can also be arranged on raised areas such as the upper part of a snap hook or guide groove or outside the magnet grid in order to enable this function if required.

[0122] The magnet device or magnet grid can have the same functionality as before, but by using lighter and / or less expensive materials or elements that are permanently attached to the magnet grid or enclosed by the magnet grid and thus can locally replace the hard magnetic material, the overall weight and / or cost is reduced.

[0123] This aspect of the invention is based on the recognition that hard magnetic materials such as neodymium iron boron have a relatively high density and usually involve relatively high raw material costs. Thus, in regions where magnetic functionality is not required, this material can be replaced by other materials with lower costs and / or densities. When the hard magnetic material is used as a filler in a plastic matrix, the same type of plastic can be used, especially in non-magnetic regions, without using the filler and thus enabling good material bonding between regions. However, other plastics, foaming materials, wood, and many other materials can also be considered. The non-magnetic regions, if they are in a plastic state, can be printed or injection molded together with the other regions using 2K manufacturing, or they can be manufactured upstream and placed as inserts in the mold or on the printing plate and integrated and firmly bonded to the hard magnetic regions during the primary molding process.

[0124] The magnet device or magnet grid can have features and / or integrated elements, such as contact surfaces, solder surfaces, bonding pads, solder lugs, etc., for electrical contact of conductor tracks located on the diaphragm film.

[0125] This aspect of the invention is based on the recognition that electrical contact between the conductor track and the lead can be difficult. This is because the conductor track and the diaphragm film are often very thin and can be temperature sensitive, resulting in the possibility that soldering or bonding may not be possible. One solution according to the invention can be to press a flat metal part, optionally in combination with a conductive adhesive, against the end of the conductor track. These contact parts or the open ends of the conductor tracks can, if necessary, be correspondingly flat and / or thick in design and can themselves enable a soldering connection to the supply line, for example, to enable a stable and easily established contact, and can be integrated as inserts into a magnet grid. This contact method can be very advantageous especially when the acoustic transducer is symmetric as described above and consists only of a diaphragm with two magnet grids and conductor tracks. If necessary, some surfaces of the contact parts can be electrically insulated, for example by painting, to prevent an electrical short circuit via the magnetic material.

[0126] The magnet device or magnet grid is mechanically reinforced and / or stiffened by its shape and / or by elements firmly connected to or surrounded by the magnet device or magnet grid to achieve a higher robustness for the required application and / or to permanently support the repulsive force in a symmetric structure consisting of two mirror magnet grids arranged close to each other.

[0127] This means that the magnet device or magnet grid for the core function of providing a magnetic field in the drive region can be relatively thin, for example, with a thickness of about 1 mm. However, in this embodiment, when a particularly large force acts on the magnet device and / or magnet grid, the hard magnetic material may be brittle and prone to breakage, so the stability and / or strength of the magnet device and / or magnet grid may be impaired. Dynamic forces can occur during use due to collisions or drops, while static forces can occur, in particular, in a symmetric structure consisting of two magnet grids repelling each other. To enhance the stability of the magnet device or magnet grid, the magnet device or magnet grid can be reinforced by appropriate structural reinforcements, struts, etc. Alternatively or additionally, other components or materials, such as inserts, 2K injection molding, carbon fiber, steel bars, metal sheets, etc., can be incorporated into the magnet device or magnet grid.

[0128] The magnet device or magnet grid can be substantially symmetric with respect to at least one axis to enable the use of a second similar magnet grid for a symmetric structure consisting of two mirror magnet grids. In the case of a symmetric structure consisting of two opposing magnet grids, it may be advantageous if the same magnet grid can be used twice. To enable the necessary 180° rotation, it may be advantageous if the magnet grid has at least one axis of symmetry by itself, apart from the individual features as described above.

[0129] The magnet device or magnet grid can have acoustic properties that affect the sound field, sound pressure, sound velocity, or sound flow in the vicinity of the acoustic transducer, or shape it according to frequency or amplitude, or affect the vibration behavior of the diaphragm film or other elements, in order to reduce or intentionally shape the non-linear distortion or frequency-dependent amplitude variation in the generated sound signal.

[0130] The magnet device or magnet grid can be designed for its complete acoustic transparency in the grid structure, i.e., the aperture degree and / or the shape of the apertures it contains. Alternatively, the diaphragm may have a defined acoustic resistance in order to achieve attenuation of unwanted vibration modes and non-linear distortion of the diaphragm. Or it may have regions that generate acoustic resonances and thus amplify or attenuate specific acoustic frequencies. Several acoustic paths with different path lengths and / or resonance frequencies can be realized in the same magnet grid so as to affect different frequency ranges. Furthermore, (additional) regions of the magnet grid can preferably be embodied as inserts or by 2K manufacturing with different, for example porous and thus acoustically absorbent materials, in order to influence the sound flow or to reduce, for example, unwanted reflections and modes. In this way, various quantities of sound pressure, velocity, flow rate, and radiation can be shaped to achieve a specific sound quality and signature.

[0131] In the region adjacent to a higher-level assembly (e.g., the housing), the magnet device or magnet grid can be made of an elastic material that provides an acoustic seal, separates structure-borne sound, and compensates for mechanical tolerances.

[0132] This aspect of the invention is based on the recognition that elastic elements such as seals made of foam or silicone are often inserted between the acoustic transducer and the housing. These elements can be integrated into the magnet grid as inserts or by 2K manufacturing as described above in order to save corresponding work steps during assembly. The purpose can be, on the one hand, a seal to prevent acoustic short-circuiting between the front and rear parts of the acoustic transducer and, on the other hand, a mechanical separation to reduce the transmission and audibility of structure-borne noise from the housing, cables, or other components to the acoustic transducer. It is also possible to compensate for possible mechanical tolerances, i.e., mechanical dimensions and properties that vary during serial production, by deforming the elastic material more or less.

[0133] The arrangement and shaping of the magnets or magnet grid, i.e., the bars and recesses, can map the path of the conductor tracks on the diaphragm film, particularly in regions such as connection pieces, sweeping portions, etc., either directly or inversely, substantially in order to concentrate the permanent magnetic field as uniformly as possible on all parts of the conductor tracks.

[0134] This aspect of the present invention is based on the recognition that conventional mounting forms use magnetic rods extending parallel to the conductor tracks. The degree of freedom in the shape of the monolithic magnet grid according to the present invention enables the sweep or connection between parallel conductor track segments to be accurately followed either directly or inversely, thus generating a constant magnetic field there and thus enabling a uniform driving force to be generated across the entire membrane surface.

[0135] The corresponding magnetic poles of the conductor tracks and the grid can extend in the direction of the longest extension of the acoustic transducer (e.g., the long semi-axis of an ellipse) in order to keep the number of parallel conductor track segments and the number of connection pieces (sweeping portions) low. Thus, based on the previous aspect, it can also be advantageous if the parallel conductor track segments and the corresponding grid structure extend in the direction of the longest extension of the acoustic transducer in order to minimize the number and length of turns or connection pieces. This simplifies the manufacture of the grid and minimizes the number of conductor track pieces that contribute little to driving the acoustic transducer in the edge region but increase the conductor length and electrical resistance and thus reduce the current and thus the driving force.

[0136] Overall, the aspects and features of the present invention mean that a relatively very small number of individual parts are required. Thus, the labor for assembly and quality assurance is very low, enabling economic manufacture at a cost level below that of conventional dynamic or moving coil acoustic transducers. Furthermore, the significantly improved sound quality of the planar dynamic acoustic transducer can be made available to a fairly wide customer base.

[0137] Some exemplary embodiments of the present invention and further advantages are shown and described in more detail below, purely schematically, in connection with the following drawings. The following are shown.

Brief Description of the Drawings

[0138]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Modes for Carrying Out the Invention

[0139] The above figures are seen in Cartesian coordinates. The longitudinal direction X is shown, which can also be called the depth X or the length X. The transverse direction Y, which can also be referred to as the width Y, extends perpendicular to the longitudinal direction X. The vertical direction Z extends perpendicular to both the longitudinal direction X and the transverse direction Y, and can also be called the height Z, corresponding to the direction of gravity. Both the longitudinal direction X and the transverse direction Y form the horizontal X, Y, which can also be referred to as the horizontal plane X, Y.

[0140] According to the first embodiment of FIG. 1, the planar dynamic acoustic transducer 0 has, in the vertical direction Z, that is, looking from bottom to top perpendicular to the horizontal X, Y, a magnet device 1, a diaphragm 2, a spacer element 3, and a protective grid 4, which in the assembled state (not shown) are held together by fixing means 5 in the form of screws 5. The screws 5 can be removed non-destructively for repair or disassembly. The planar dynamic acoustic transducer 0 or its corresponding elements, components, or structural parts are substantially flat or planar in the horizontal directions X, Y, where it extends elliptically with the longitudinal direction X as the preferred extension direction.

[0141] The magnet device 1, which can also be called the magnet grid 1, is integrally formed, that is, integrally or as a single magnet body 1. The magnet device 1 has an internal region 11, which in the first embodiment is formed as a recess 11 facing the edge region 14. In this internal region 11, a magnetic bar 12 having magnetic poles and an acoustic aperture 13 are formed, which extend parallel to the magnetic bar 12 in the longitudinal direction X, surround the magnetic bar 12 at one end, and are spaced apart from each other in the transverse direction Y. The magnetic bars 12 are connected to each other at the opposite ends via the edge region 14 already described.

[0142] The diaphragm 2, which is preferably formed as a relatively thin diaphragm film 2 with a thickness of less than 10 μm, is also integrally formed by a diaphragm body 20 made of a flexible material. A conductor track 21 made of a conductive material is applied to the diaphragm 2, and this conductor track 21 extends in alignment with the acoustic aperture 13 of the magnet device 1. Therefore, the longitudinal portion 21a of the conductor track 21 extends parallel to the acoustic aperture 13 in the longitudinal direction X, and the sweeping portion 21b of the conductor track 21 surrounds the open end of the magnetic bar 12 in the transverse direction Y.

[0143] The spacer element 3, which can also be referred to as the first ring 3, has a spacer element body 30, and the spacer element body 30 is also integrally formed. Since the spacer element 3 has an elliptical internal region 31 as a through-opening without material in the vertical direction Z or perpendicular to the horizontal directions X, Y, the spacer element body 30 surrounds the elliptical and hollow internal region 31.

[0144] As shown in FIG. 1, the protective grid 4 closes the planar dynamic acoustic transducer 0 in the vertical direction Z or perpendicular to the horizontal directions X, Y. The protective grid 4 is also integrally formed as a protective grid body 40. In the internal region (not shown), the protective grid body 40 has a plurality of acoustic apertures 41, and each of the acoustic apertures 41 is circular, uniformly distributed, and surrounded by the protective grid body 40.

[0145] According to the present invention, the edge region 14 has additional mechanical, acoustic, and electrical functions. This can extend the range of functions of the planar dynamic acoustic transducer 0, improve its characteristics or quality, and / or simplify its manufacturing, particularly its assembly.

[0146] As a mechanical function of the planar dynamic acoustic transducer 0, the holding of elements, components, or structural parts is improved according to the present invention in that the edge region 14 of the magnet device 1 has a plurality of receiving portions 15 evenly distributed in the circumferential direction in the form of holes 15 each having a female thread capable of receiving the corresponding male thread of the screw 5. This enables simple and safe assembly. The diaphragm 2 has corresponding through openings 22 for the fixing means 5 or the screw 5 on the edge side, the spacer element 3 has corresponding through openings 32 for the fixing means 5 or the screw 5 on the edge side, and the protective grid 4 has corresponding through openings 42 for the fixing means 5 or the screw 5 on the edge side, and these are aligned with each other in the attached state so that the screw 5 can reach the receiving portion 15 of the edge region 14 of the magnet device 1. This enables easy assembly with secure holding.

[0147] In order to align the receiving portion 15 of the edge region 14 of the magnet device 1 with the through opening 22 for the fixing means 5 or the screw 5 of the diaphragm 2, the through opening 32 for the fixing means 5 or the screw 5 of the spacer element 3, and the through opening 42 for the fixing means 5 or the screw 5 of the protective grid 4 as simply, quickly, and surely as possible, the edge region 15 of the magnet device 1 further has a pair of guide keys 16 in the form of guide pins 16 positioned opposite each other in the diametrical direction. The diaphragm 2 has a corresponding pair of through openings 23 for the guide keys 16 of the magnet device 1. Accordingly, the spacer element 3 also has a pair of through openings 33 for the guide keys 16 of the magnet device 1. Accordingly, this applies to the protective grid 4, and then the protective grid 4 has a pair of through openings 43 for the guide keys 16 of the magnet device 1.

[0148] Since these through openings 23, 33, 43 for the guide keys 16 of the magnet device 1 are also arranged corresponding to each other, the diaphragm 2, the spacer element 3, and finally the protective grid 4 can be positioned and held aligned with each other one after another or together by the guide keys 16 of the magnet device 1, and as a result, the screw 5 can be screwed in as described above. This can further simplify the assembly, particularly the positioning and alignment.

[0149] According to the present invention, the electrical function of the planar dynamic acoustic transducer 0 is to enable the conductor track 21 of the diaphragm 2 to contact the edge region 14 of the magnet device 1. For this purpose, the two conductor track ends 21c are formed flat as the contact points 21c of the conductor track 21 and are connected by a conductive adhesive to the corresponding contact element 17 or the corresponding contact surface 17 for the conductor track 21 of the diaphragm 2 in the vertical direction Z or downward perpendicular to the horizontal directions X and Y. As a result, there is an electrical connection between the diaphragm 2 and the magnet device 1 at these two points. The two contact surfaces 17 for the conductor track 21 of the diaphragm 2 of the magnet device 1 are conductively connected to the outer contact elements 18 of the magnet body 1 in the form of outer contact pins 18 directed radially outward from the edge region 14 of the magnet device 1 via the magnet body 10.

[0150] The two outer contact pins 18 of the edge region 14 of the magnet device 1 supply power to the conductor track 21 of the diaphragm 2. Therefore, in order to operate the planar dynamic acoustic transducer 0, the two outer contact pins 18 of the edge region 14 of the magnet device 1 are soldered so that electrical contact can be made from the outside of the planar dynamic acoustic transducer 0. This makes it possible to omit direct electrical contact from the outside of the conductor track end 21c of the conductor track 21 of the diaphragm 2, thereby enabling the conductor track 21 of the diaphragm 2 or the diaphragm 2 to be formed relatively thin or delicate and still be able to make electrical contact.

[0151] In any case, the magnet body 10 of the magnet device 1 can be integrally formed, for example, by a two-component injection molding method (2K injection molding method). As a result, a plastic material such as polyamide exists in the internal region, and a permanent magnet or hard magnetic particles such as those made of neodymium iron boron are embedded in the internal region. Using the 2K method, this internal region 11 of the magnet body 1 is integrally surrounded only by the same plastic material so that the edge region 14 of the magnet body 1 does not contain hard magnetic particles. Thereby, the desired magnetic characteristics of the magnet device 1 can be achieved in its internal region 11. At the same time, since the hard magnetic particles in the edge region 14 of the magnet body 1 can be saved, the manufacturing cost of the magnet arrangement 1 can be kept low with respect to the material of the magnet device 10.

[0152] The planar dynamic acoustic transducer 1 of the second embodiment example in FIG. 2 substantially corresponds to the planar dynamic acoustic transducer 1 of the first embodiment example in FIG. 1.

[0153] However, the elements, components, or structural parts of the planar dynamic acoustic transducer 1 of the second embodiment example in FIG. 2 are held in place by the fact that four snap-in hooks 19 are integrally formed on the edge region 14 of the magnet device 1 of the magnet body 1, which may also be called snap-in hooks 19 and extend upward in the vertical direction Z or perpendicular to the horizontal directions X and Y. The hook elements (not shown) of the snap hook 19 project radially inward, and the upper surface (not shown) of the hook element is formed to extend obliquely inward. The four snap hooks 19 are substantially arranged at the four corners of the elliptical surface of the magnet device 1.

[0154] Since the edge region 14 of the magnet device 1 is flat or flat with the inner region 11, the distance between the magnet devices 1 above the diaphragm 2 in the vertical direction Z or perpendicular to the horizontal directions X, Y is achieved by additional elements, components, or structural parts in the form of the integral support element 6. Since the support element 6 houses the diaphragm 2, it can also be called the housing element 6 or the second ring 6. The support element 6 also has an elliptical inner region 61 as a through-opening without material in the vertical direction Z or perpendicular to the horizontal directions X, Y, so that the support element body 60 surrounds the hollow inner region 61 in an elliptical shape.

[0155] Here, the elements, components, or structural parts of the planar dynamic acoustic transducer 1 of the second embodiment example in FIG. 2 are assembled such that the support element 6 is first pressed against the magnet device 1 from above, and the snap hook 19 is elastically bent radially outward in a spring-like manner to allow the support element body 60 to pass between them. This is also continuously done with respect to the diaphragm 2, the spacer element 3, and the protective grid 4. Then, the protective grid 4 is gripped from above by hook elements protruding radially inward in the vertical direction Z or perpendicular to the horizontal directions X, Y, and thus held. This means that the assembly can be carried out without additional fixing means 5 or screws 5, which simplifies the assembly and can save material costs.

[0156] A secure hold perpendicular to the vertical direction Z or the horizontal directions X, Y can be achieved, if necessary, by forming the support element 6 and / or the spacer element 3 from an elastic material in order to apply a specific force from the inside or from below in a direction perpendicular to the vertical direction Z or the horizontal directions X, Y to the hook elements of the snap hook 19. This can also compensate for the manufacturing tolerances of these elements, components, or structural parts perpendicular to the vertical direction Z or the horizontal directions X, Y.

[0157] The simple and reliable positioning of the elements, components, or structural parts of the planar dynamic acoustic transducer 1 of the second embodiment example in FIG. 2 corresponds to the arrangement of the snap-in hook 19, and thus can be achieved by the elliptical design of the contour of the elements, components, or structural parts that enables the assembly as described above only in two mirror-symmetrical arrangements. The elements, components, or structural parts of the planar dynamic acoustic transducer 1 can be designed accordingly.

[0158] In addition, the upper end of the snap hook 19, which can be called the snap hook head 19a or the latching hook head 19a, can be designed to be permanently magnetic towards the top so that other elements, components, or structural parts of the product in which the planar dynamic acoustic transducer 1 is used or installed can be magnetically removably connected to the planar dynamic acoustic transducer 1 of the second embodiment example in FIG. 2. Thereby, the assembly of the product can be simplified and / or further usability can be created.

[0159] In any case, the possibility of electrical contact of the conductor track 21 of the diaphragm film 2 described with respect to the first embodiment example of the planar dynamic acoustic transducer 1 in FIG. 1 can also be used in the second embodiment example in that the support element 6 has a pair of contact elements 62 or contact surfaces 62 for the conductor track 21 of the diaphragm film 2 and a pair of outer contact elements 63 or outer contact pins 63. This means that the corresponding electrical functions can also be implemented and used in the second embodiment example described above.

[0160] As an acoustic function, the magnet device 1 or the magnet grid 1 affects the sound field, sound pressure, sound velocity, or sound flow in the environment of the planar dynamic acoustic transducer 1 with respect to the specific configuration and arrangement of the acoustic aperture 13 and the magnetic bar 12 or their magnetic poles, and can be shaped based on frequency or amplitude, or affects the vibration behavior of the diaphragm film 2 or other elements so that non-linear distortion or frequency-dependent amplitude variation in the generated sound signal can be reduced or intentionally shaped. For this purpose, the grid structure of the magnetic bar 12 of the magnet device 1 can be designed for complete acoustic transparency with respect to the aperture degree and / or shape of the acoustic aperture 13. However, alternatively, the acoustic aperture 13 of the magnet device 1 can also have a defined acoustic resistance to achieve attenuation of unwanted vibration modes and non-linear distortion of the diaphragm 2. Alternatively, the acoustic aperture 13 of the magnet device 1 may have regions that generate resonance and / or reflection, thereby amplifying or attenuating specific acoustic frequencies.

[0161] According to the illustration of FIGS. 3 and 4, this can be implemented specifically, for example, by introducing the horizontal cavity 12a of the magnetic bar 12 along the internal region 11 and the horizontal cavity 14a of the edge region 14 along the longitudinal direction X or parallel to the longitudinal direction X of the edge region 14 as the maximum extension of the planar dynamic acoustic transducer 1. Similarly, the horizontal cavity 12a of the magnetic bar 12 can also extend in the lateral direction Y. In any case, sound can enter the cavity from the acoustic aperture 13 of the magnet device through the horizontal cavity 12a of the magnetic bar 12 in the longitudinal direction X, through the horizontal cavity 12a of the magnetic bar 12 in the lateral direction Y, and through the horizontal cavity 14a of the edge region 14 in the longitudinal direction X, and vice versa. For this purpose, apertures are provided at selected positions in these cavities 12a, 14a through which the sound flow can enter and exit.

[0162] In this way, as the acoustic functions of the magnet device 1, particularly its edge region 14 and / or its interior 11, resonances and / or reflections can occur at specific acoustic frequencies whose wavelengths are in a specific ratio to the respective cavity lengths and / or the respective aperture distances, and these are superimposed on the regular acoustic radiation of the planar dynamic acoustic transducer 1. This superposition is constructive or destructive depending on the phase position and spatial arrangement of the resonances. This results in amplification or attenuation of the sound emitted externally at these frequencies.

[0163] FIG. 5 is a perspective sectional view of the magnet device 1 of the planar dynamic acoustic transducer 0 according to a fourth exemplary embodiment from obliquely above. FIG. 5 is a perspective view of the magnet device 1 in which the edge region 14 is formed in the baffle 10a, and the baffle 10a significantly prevents acoustic short - circuiting between the front and rear parts of the diaphragm in the relevant frequency range. Here, 11 indicates an internal region having a grid structure formed by magnetic bars 12 materially connected to non - magnetic bars 12b.

[0164] FIG. 6 is a perspective sectional view of the magnet device 1 of the planar dynamic acoustic transducer 0 according to a fifth exemplary embodiment from obliquely below. FIG. 6 is a perspective view of the magnet device 1, and the edge region 14 of the magnet device 1 is formed in a front - part housing shell having a circumferential side wall 14b and a hole 15. The hole 15 can accommodate, for example, a screw, and by using the screw, the front - part housing shell can be connected to the rear - part housing shell 7 to obtain a closed housing.

[0165] FIG. 7 is a perspective cross-sectional view from an obliquely upper side of a magnet device 1 of a planar dynamic acoustic transducer 0 according to a sixth embodiment example. FIG. 7 is a perspective view of the magnet device 1, and an edge region 14 of the magnet device 1 is formed in a front housing shell having a circumferential side wall 14b and a hole 15 that can accommodate, for example, a screw, and the screw can be used to connect the front housing wall or shell to a rear housing wall or shell (not shown) to obtain a closed housing. A further wall 14c, together with a rear housing wall not shown, forms an acoustic channel of a defined length, and the acoustic channel supplies acoustic energy from the rear of the diaphragm through a first aperture 14d to an acoustic outlet 14e, delays the acoustic energy due to the acoustic propagation time, and / or generates a standing wave, whereby the radiated acoustic energy of the entire system can be affected based on the excitation frequency. Here, 14f indicates a raised contact surface for the diaphragm.

[0166] FIG. 8 is a perspective cross-sectional view from an obliquely upper side of a magnet device 1 of a planar dynamic acoustic transducer 0 according to a seventh embodiment example. FIG. 8 is a perspective view of the magnet device 1, and an edge region 14 of the magnet device 1 is formed in a front housing shell having a circumferential side wall 14b and a hole 15 that can accommodate, for example, a screw, and the screw can be used to connect the front housing wall or shell to a rear housing wall or shell (not shown) to obtain a closed housing. Two further walls 14c, together with a rear housing wall not shown, form an acoustic channel of a defined length, which surrounds an acoustic mass for a resonance system between a first aperture 14d and an acoustic outlet 14e.

[0167] FIG. 9 is a perspective sectional view of the magnet device 1 of the planar dynamic acoustic transducer 0 according to an eighth embodiment example from an obliquely upper direction. FIG. 9 is a perspective view of the magnet device 1, and the edge region 14 of the magnet device 1 is formed in a front housing shell having a circumferential side wall 14b and a hole 15 that can accommodate, for example, a screw. The screw can be used to connect the front housing wall or shell to a rear housing wall or shell (not shown) to obtain a closed housing. The edge region 14 has an additional internal region 11a smaller than the first internal region 11 and an additional raised contact surface 14h for an additional diaphragm. The additional acoustic transducer thus formed is more suitable for reproducing higher acoustic frequencies than the acoustic transducer formed by the first internal region 11, the diaphragm support 14f, and the associated first diaphragm because its dimensions are reduced.

[0168] FIG. 10 is a perspective sectional view of the magnet device 1 of the planar dynamic acoustic transducer 0 according to a ninth embodiment example from an obliquely upper direction. FIG. 10 shows the magnet device 1 from FIG. 9, and the magnet device 1 forms a housing having a sealed air volume together with a rear housing wall not shown. The housing is divided by an additional wall 14i into two separate air volumes respectively assigned to the first internal region 11 and the additional internal region 11a.

[0169] FIG. 11 is a perspective sectional view of the magnet device 1 of the planar dynamic acoustic transducer 0 according to a tenth embodiment example from an obliquely upper direction. Here, the internal region 11 is formed from several material components processed in the same manufacturing process such as an injection molding process. In particular, the magnetic bar 12 is an embodiment with a strength necessary to provide a one-sided multipole magnetic field in the Z direction. The magnetic bar 12 is mechanically supported or carried by a further bar 12b made of a non-magnetic material, and the bar 12b is substantially aligned horizontally and adjacent vertically.

[0170] FIG. 12 is a perspective sectional view from diagonally above of a magnet device 1 of a planar dynamic acoustic transducer 0 according to an eleventh exemplary embodiment. 14 indicates an edge region, and this edge region also provides a raised contact surface 14f for the diaphragm. 11 indicates an internal region having a grid structure, and the outer aperture or slot 13a has a width smaller than that of the inner aperture or slot 13b in order to concentrate acoustic radiation on the inner aperture and convert a planar sound source into a substantially linear or point sound source.

[0171] FIG. 13 is a perspective sectional view of a magnet device 1 of a planar dynamic acoustic transducer 0 according to a twelfth exemplary embodiment from diagonally above. FIG. 14 shows FIG. 13 from below. FIGS. 13 (upper side) and 14 (lower side) show the magnet device 1 of FIG. 9 having different shapes of acoustic channels formed by side walls 14b and further walls 14c. The edge region 14 continues outside the side wall 14b and thus merges seamlessly with a surface 14g shown here only in a simplified form as a circular flat disk, which is part of a larger structure. However, it can be shaped in almost any way, for example, it can form a screen housing or the rear wall of a lighting fixture, the outer surface of a part of furniture or a ceiling suspension, or the door, roof, dashboard, luggage rack, footwell or seat trim surface of a vehicle. Further lining is not affected, for example, by attaching foil, lining material or interior foam, but should be embodied in an acoustically transparent way in the region of the sound outlet. This integration into a continuous larger structure requires that the sound outlet 14e is located substantially in the plane of the internal region 11 and thus emits sound externally on the same side as the acoustic transducer. This is appropriately applied when using a delay channel as shown in FIG. 9.

Description of Reference Numerals

[0172] X Longitudinal depth length Y Lateral width Z Vertical direction, height X, Y Horizontal, horizontal plane 0 Planar dynamic acoustic transducer 1 Magnet device, magnet grid, magnet system 10 Magnet body 10a Baffle 11 Inner region recess 11a Additional inner region 12 Magnetic bar 12a (Horizontal) cavity in the inner region 11 or the magnetic bar 12 12 Non-magnetic bar 13 Acoustic aperture of the magnet device 1 13a Acoustic aperture of smaller width of the magnet device 1 13b Acoustic aperture of larger width of the magnet device 1 14 Edge region 14a (Horizontal) cavity in the edge region 14 14b Side wall of the edge region 14 14c Further wall of the edge region 14 (acoustic channel) 14d First aperture of the edge region 14 (acoustic channel) 14e Acoustic outlet of the edge region 14 (acoustic channel) 14f Enlarged contact surface for the diaphragm of the edge region 14 14g Surface of the edge region 14 (part of a larger structure) 14h Additional raised contact surface 14 for an additional diaphragm of the edge region 14i Additional wall of the edge region (separation of air volume) 14 15 Hole having a female thread for the housing of the fixing means 5 16 Guide groove, guide pin 17 Contact element or contact surface for the conductor track 21 of the diaphragm 2 18 External contact element or external contact pin 19 Snap hook, snap-in hook 19a Snap hook head, snap-in hook head 2 Diaphragm, diaphragm film 20 Diaphragm body 21 Conductor track 21a Longitudinal part of the conductor track 21 21b Sweeping part of the conductor track 21 21c Conductor track end, contact point of the conductor track 21 22 Through-hole opening for the fixing means 5 23 Through-hole opening for the guide key 16 of the magnet device 1 3 Spacer element, first ring 30 Spacer element body 31 Hollow inner region 32 Through-hole opening for the fixing means 5 33 Through-hole opening for the guide key 16 of the magnet device 1 4 Protection grid 40 Protection grid body 41 Acoustic aperture of the protection grid 4 42 Through-hole opening for the fixing means 5 43 Through-hole opening for the guide key 16 of the magnet device 1 5 Fixing material, screw 6 Support element, housing element second ring 60 Support element body 61 Hollow inner region 62 Contact element or contact surface for the conductor track 21 of the diaphragm 2 63 External contact element or external contact pin 7 Rear housing shell

Claims

1. A planar dynamic acoustic transducer (0), A magnet device (1) having multiple magnetic poles and at least one acoustic aperture (13), It has a diaphragm (2) having at least one conductor track (21), The magnet device (1) has an internal region (11) including the magnetic poles and an edge region (14) that surrounds the internal region (11) and connects the elements of the internal region (11) to each other. The internal region (11) of the magnet device (1) is preferably arranged to coincide with the conductor track (21) of the diaphragm (2) so as to be offset perpendicular to the horizontal (X, Y) from the conductor track (21) of the diaphragm (2), and to at least overlap with the conductor track (21) of the diaphragm (2) in the horizontal (X, Y) direction. The edge region (14) of the magnet device (1) further includes at least one mechanical, acoustic, and / or electrical function of the planar dynamic acoustic transducer (0), In the aforementioned planar dynamic acoustic transducer (0), The internal region (11) and the edge region (14) of the magnet device (1) are monolithically formed by the magnet body (10). At least the internal region (11) of the magnet device (1), preferably precisely the internal region (11) of the magnet device (1), has a hard magnetic material, preferably made of a hard magnetic material. A planar dynamic acoustic transducer (0) characterized by the following:

2. The edge region (14) of the magnet device (1) is formed from a different material than the internal region (11) of the magnet device (1), preferably from a material having a lower specific gravity, and / or from a material having lower magnetization or no magnetization, and / or from an elastic material. Planar dynamic acoustic transducer (0) according to claim 1.

3. The internal region (11) of the magnet device (1) is formed from a first material in a first method step, and the edge region (14) of the magnet device (1) is subsequently formed from a second different material in a second method step. Planar dynamic acoustic transducer (0) according to claim 1 or 2.

4. A portion of the edge region (14), preferably the internal region (11), of the magnet device (1) is formed from a first material in a first method step, and thereafter, the preferably remaining internal region (11) of the magnet device (1) is formed from a second different material in a second method step. Planar dynamic acoustic transducer (0) according to claim 1 or 2.

5. The edge region (14) comprises at least partially an elastic material, preferably partially formed from a third different elastic material in the third method step. Planar dynamic acoustic transducer (0) according to claim 1 or 2.

6. The edge region (14) of the magnet device (1) perpendicular to the horizontal (X, Y) is higher than the internal region (11) of the magnet device (1). Preferably, the diaphragm (2) is in direct contact with the edge region (14) of the magnet device (1). Planar dynamic acoustic transducer (0) according to claim 1 or 2.

7. The magnet device (1) comprises at least one support element (6) positioned perpendicular to the horizontal (X, Y) between the edge region (14) and the diaphragm (2), wherein the hollow internal region (61) separates the internal region (11) of the magnet device (1) from the diaphragm (2), Planar dynamic acoustic transducer (0) according to claim 1 or 2.

8. The edge region (14) of the magnet device (1) has at least one guide tenon (16), preferably a pair of guide tenons (16), and the diaphragm (2), preferably a support element (6) and / or a spacer element (3) and / or a protective grid (4) has at least one through-opening (23), preferably a pair of through-openings (23) for the guide tenons (16) of the magnet device (1). Planar dynamic acoustic transducer (0) according to claim 1 or 2.

9. The edge region (14) of the magnet device (1) has at least one housing portion (15), preferably a plurality of housing portions (15), for housing a fixing means (5), preferably a screw (5). The diaphragm (2), preferably the support element (6) and / or the spacer element (3) and / or the protective grid (4), has at least one through-opening (22), preferably a plurality of through-openings (22), for the fixing means (5). Planar dynamic acoustic transducer (0) according to claim 1 or 2.

10. The edge region (14) of the magnet device (1) has at least one snap hook (19), preferably a plurality of snap hooks (19), for engaging around the diaphragm (2), preferably a spacer element (3) or protective grid (4), Preferably, the snap hook head (19a) facing away from the magnet device (1) is magnetically formed. Planar dynamic acoustic transducer (0) according to claim 1 or 2.

11. The edge region (14) has at least one preferably horizontal cavity (14a), preferably a plurality of preferably horizontal cavities (14a), and the cavities (14a) are preferably open to at least one acoustic aperture (13), particularly preferably a plurality of acoustic apertures (13). The length of the cavity (14a) and / or the distance between the two apertures of the cavity (14a) are selected such that at least one acoustic frequency whose wavelength is in a predetermined ratio to the length of the cavity (14a) and / or the distance between the two apertures of the cavity (14a) resonates and / or is reflected. Planar dynamic acoustic transducer (0) according to claim 1 or 2.

12. The internal region (11), preferably at least one magnetic web (12) of the internal region (11), more preferably several magnetic webs (12), most preferably all magnetic webs (12), has at least one, preferably horizontal cavity (12a), preferably several, preferably horizontal cavity (12a), and the cavity (12a) opens to preferably at least one acoustic aperture (13), more preferably several acoustic apertures (13). The length of the cavity (12a) and / or the distance between the two apertures of the cavity (12a) are selected such that at least one acoustic frequency whose wavelength is in a predetermined ratio to the length of the cavity (12a) and / or the distance between the two apertures of the cavity (12a) resonates and / or is reflected. Planar dynamic acoustic transducer (0) according to claim 1 or 2.

13. The internal region (11) is partially acoustically more transparent to particularly high acoustic frequencies, and otherwise is not acoustically more transparent to particularly high acoustic frequencies, and / or It has a pair of mirror-symmetrical magnet devices (1) surrounding the diaphragm (2) perpendicular to the horizontal (X, Y), and / or The magnet device (1) has magnetic poles and has at least one further internal region (11a) surrounded by the edge region (14), Preferably, the edge region (14) of the magnet device (1) extends substantially outward in a horizontal (X, Y) direction and has at least one additional wall (14f) that acoustically separates the internal region (11) of the magnet device (1) from the further internal region (11a). Planar dynamic acoustic transducer (0) according to claim 1 or 2.

14. The magnet device (1) has no magnetic poles and has at least one further internal region (11) surrounded by the edge region (14), and / or The edge region (14) of the magnet device (1) is formed as a baffle (10c), and / or The edge region (14) of the magnet device (1) extends substantially outward in the horizontal (X, Y) direction and has at least one wall (14b) that at least partially surrounds at least one internal region (11, 11a). Planar dynamic acoustic transducer (0) according to claim 1 or 2.

15. The edge region (14) of the magnet device (1) extends substantially outward in a horizontal (X, Y) direction and has at least one wall (14c) that forms at least one acoustic channel, the acoustic channel being designed to be in acoustic communication with the air volume above the internal region (11) and the ambient atmosphere. Planar dynamic acoustic transducer (0) according to claim 1 or 2.

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