Planar-dynamic acoustic transducer

Abstract

The present invention relates to a planar-dynamic acoustic transducer (0) having at least one magnet arrangement (1) having a plurality of magnetic poles and having at least one acoustic aperture (13) and having a diaphragm (2) having at least one conductor track (21), wherein the magnet arrangement (1) has an inner region (11), which includes the magnetic poles, and an edge region (14), which surrounds the inner region (11) and connects the elements thereof to one another, wherein the inner region (11) of the magnet arrangement (1) is arranged in a manner offset from the conductor track (21) of the diaphragm (2) perpendicular to the horizontal (X, Y) and in a manner at least overlapping, preferably congruent, 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 edge region (14) of the magnet arrangement (1) furthermore includes at least one mechanical, acoustic and / or electrical function of the planar-dynamic acoustic transducer (0).

Description

[0001] DESCRIPTION

[0002] Planar dynamic transducer

[0003] The present invention relates to a planar dynamic sound transducer.

[0004] To generate sound, for example, in loudspeakers, so-called transducers are used as sound sources. These transducers convert electrical voltage into acoustic signals. Conversely, a transducer can also convert acoustic signals as alternating sound pressures into electrical signals or electrical voltage, which is implemented, for example, in microphones. This can be achieved according to different principles.

[0005] 1. Dynamic transducers

[0006] Today, electrodynamic or dynamic loudspeakers, which operate according to the electrodynamic principle, are widespread. Accordingly, an electrical conductor is placed in a magnetic field. Either a magnetic field coil or a permanent magnet can be used to generate the magnetic field. If the electrical conductor is then energized, the Lorentz force causes a mechanical movement of the electrical conductor, which depends on the direction of the current. The mechanical movement of the electrical conductor is transferred, usually with the help of a membrane element, to the surrounding air, where it generates sound waves as acoustic signals. The detection of sound waves can be reversed and is used, for example, in microphones.

[0007] Widely used are dynamic sound transducers with a cone-shaped design. These consist of a magnet system (also called a magnet assembly), a voice coil, a shaped diaphragm, a suspension, and a housing or chassis. Depending on how the magnetic field is generated, they can be referred to as electrodynamic cone speakers or permanent-magnet cone speakers. In either case, the conical design of the diaphragm and the cylindrical shape of the voice coil result in a comparatively high structure in the direction of sound emission and thus in a comparatively large installation space. The components of such dynamic sound transducers also result in a considerable weight. The sound is generated over a rather small area or at a specific point, which does not correspond to natural sound waves.In addition, the tight mechanical tolerances required between the coil and the magnet system as well as the complex construction of the aforementioned and other individual parts result in considerable development and manufacturing costs.

[0008] Nevertheless, sound transducers based on the described, established dynamic sound transducer principle dominate in commercial products, although dynamic sound transducers have disadvantages in performance and sound quality, which can only be mitigated with great effort.

[0009] For example, the diaphragm can be made flat; however, in this design it is more prone to unwanted natural vibrations or modes and must be additionally mechanically damped and stiffened, which increases the moving mass, whose inertia impairs the reproduction of high sound frequencies. Simplifying the magnet system, for example by omitting the pole plate or by positioning the voice coil deeper in the magnet system, leads to a less focused, inhomogeneous magnetic field that is asymmetrical with respect to the rest position of the diaphragm, which leads to lower efficiency and increased nonlinearities and acoustic distortion. Approaches that generate the driving force radially to the diaphragm axis and mechanically redirect it to the axial direction, see e.g. WO 2011 / 013223 A1, lead to an even more complex design, associated with greatly increased costs for the components and their assembly.

[0010] US 2015 / 256912 A1 shows an example of a dynamic loudspeaker with a flat diaphragm that is integrally incorporated into a larger structure. A trim panel of an automobile interior has an opening into which a flat loudspeaker diaphragm, consisting of a circumferential elastic surround and a rigid diaphragm panel, is inserted. Bridge-shaped struts are attached to the back of the trim panel, spanning the diaphragm opening and centrally mounted to an electromagnetic actuator whose voice coil deflects the diaphragm from its rest position to generate sound. Certain advances can be observed here with regard to the overall depth and complexity of the assembly; however, the previously mentioned disadvantages of a flat diaphragm design also exist, and a large number of individual components are still required, which must be prefabricated separately and then assembled.

[0011] 2. Electrostatic transducers

[0012] Another known sound conversion principle is electrostatic systems consisting of one or two flat electrode grids and a flat, stretched membrane film positioned between them. With the help of a comparatively high polarization voltage, which is modulated by the desired signal, electrostatic forces are generated between the membrane and the electrodes, which deflect the membrane normal to the surface and generate sound. The objectives of the flat design and the comparatively simple construction, which are relevant for many applications, are achieved here. Therefore, the prior art includes applications of this principle for sound reinforcement in the interior of an automobile, e.g. in DE102006045385A1. However, during operation there is a risk that the membrane comes into contact with one of the electrodes due to excessive deflection or external air pressure fluctuations and adheres to it electrostatically until the polarization voltage is switched off.

[0013] To reduce this risk of interruption, other measures are required, such as additional electrical insulation, multi-layer diaphragm construction, or high mechanical diaphragm tension. These increase manufacturing costs and impair acoustic performance (reduced efficiency, mass damping of high vibration frequencies, reduced bass reproduction due to the high fundamental resonance frequency). Furthermore, disadvantages arise due to the electrical polarization voltage, which typically amounts to several hundred volts. In the event of a fault, this can pose a danger or impairment to persons or technical systems. Furthermore, parasitic electrical effects in the supply lines lead to a significant voltage drop, which depends on the line length and must be compensated for with technical effort, for example, through even higher source voltages or complex line designs.Alternatively, the high-voltage source can be positioned in the immediate vicinity of the transducer, but this requires additional power cables and additional installation space. Therefore, each of these options has significant disadvantages, especially in applications such as the interior of a motor vehicle.

[0014] 3. Surface oscillator

[0015] Another approach is pursued with surface vibrators, bending wave transducers, and similar systems. Here, a flat solid body is excited by one or more point actuators to vibrate or produce bending waves, which in turn lead to sound radiation.

[0016] The disadvantage here is that considerable design and signal processing measures are required to achieve sufficiently controlled acoustic behavior in the vibrating surface. At the frequencies corresponding to the surface's eigenmodes, excessive or nonlinear resonance must not occur, and the sound radiation power should drop as little as possible between these frequencies. This latter requirement is technically challenging due to the comparatively large vibrating mass, especially at high frequencies.

[0017] Particularly efficient use of space is achieved when existing surfaces, e.g. from screens, furniture, vehicle interior trim or body parts, are used. Examples of this are US 6,181,797 B1 (automobiles) and US 6,332,029 B1 (screens and other applications). However, this multiple use requires functional and design compromises. For example, the shape, assembly, thickness and material composition as well as the positioning of the actuators can generally only be optimized for acoustic performance to a very limited extent and the required vibrations can be detrimental to the original function or the longevity of the flat component. In addition, there are long-term signs of aging of the component that can significantly impair its vibration properties, e.g. changes in elasticity (embrittlement or softening), mechanical tolerances or coupling orConnection with neighboring components.

[0018] 4. Planar dynamic principle

[0019] Planar dynamic sound transducers have also been known for some time. These essentially consist of one or two planar magnet arrays, with a membrane with conductor tracks positioned parallel to or between them. When current flows through them, the electrically conductive tracks interact with the field of the multipole magnet arrays and generate a force acting normal to the membrane plane, causing the membrane to elastically deflect, generating air displacement and thus sound pressure.

[0020] This allows planar dynamic transducers to be constructed thinner than conical dynamic transducers, although planar dynamic transducers have a greater length and width in the diaphragm plane. However, the larger radiating surface of planar dynamic transducers requires less deflection and is therefore subject to less distortion. Furthermore, a comparatively large-area sound radiation is achieved, which better corresponds to the conditions in natural sound fields than the more point-like sound source represented by a conical dynamic transducer. A further advantage of planar dynamic transducers is the generally significantly lower mass of the diaphragm foil and the flat conductor tracks, which can result in improved radiation behavior of impulses, transients, and high-frequency components.

[0021] In other words, planar dynamic sound transducers, which are also known as orthodynamic or isodynamic sound transducers, have a flat membrane with electrical conductors on it, which is located parallel to and at a short distance from a magnet arrangement. The magnet arrangement generates a multi-pole magnetic field such that the field lines in the area of ​​the conductors run tangential to the membrane and perpendicular to the conductors. When current flows in the latter, a force is created that acts normal to the membrane, causing it to deflect and generate sound. Such a sound transducer can be used in loudspeakers and headphones as a sound generator, and in the opposite operating mode, i.e. when the membrane is deflected by sound and thus an alternating current is induced, it can also be used as a microphone. In planar dynamic sound transducers, the magnet arrangements usually consist of numerous components, including magnetic bars or-rings, support frames, stiffeners, adhesives and the like, which are to be manufactured individually and assembled.

[0022] Conventional magnet arrangements in planar dynamic sound transducers, for example, use simple bar magnets with a north pole on one long side and a south pole on the opposite long side. These pre-magnetized bars must be placed in a holder with alternating orientations and glued to it, which involves assembly effort and material consumption. Additional components such as spacers, contact elements, and the like are typically added.

[0023] In each case, the final step is to assemble the aforementioned components into the planar dynamic sound transducer, which in turn is installed in the final product, such as a loudspeaker, headphones, microphone, etc. In addition to mounts, frames, screw connections, and the like, acoustically effective components such as fabrics, resonators, foams, or so-called acoustic metamaterials are used.

[0024] 5. Planar dynamic principle with separate magnets

[0025] US 5,901,235 A describes a planar magnetic transducer with membranes on which electrical conductors are located, which are mounted in frames so that spaced magnets are arranged on opposite sides of the central sound-generating surface areas of the membranes by means of metallic support grids.

[0026] US 2015 110 339 A1 describes a planar electroacoustic multi-diaphragm transducer with a plurality of diaphragms arranged in one or more diaphragm modules. Each diaphragm module comprises at least one diaphragm, each of which is held in tension by a frame.

[0027] US 2018 / 0084346 A1 describes a planar loudspeaker unit comprising a housing, a first set of magnets, and a diaphragm. The housing has a receiving space and a bottom wall. The first set of magnets is arranged on the bottom wall and located in the receiving space. The diaphragm is arranged in the receiving space and located above the first set of magnets. The diaphragm comprises a substrate and a planar coil. The planar coil is mounted flat on the substrate.

[0028] US 10,003,876 B2 describes a planar magnetic headphone consisting of a single

[0029] Layer of parallel elongated magnets spaced apart from each other and arranged on a

[0030] The magnet holder matrix rests on a metal permeability plate. The holder matrix can be made of plastic or a metallic permeability plate, with the magnets located on the inside (toward the ear) of the plate. On the inside of the magnets is a plastic damping matrix supporting a first continuous disc-shaped damping membrane. A serpentine-shaped conductor track is attached to a thin membrane located outside the magnets, exciting the magnets and moving the membrane to generate sound according to the current in the conductor track. Further outside the conductor track and attached to an outer hard plastic cover is a second continuous disc-shaped damping membrane.

[0031] DE 10 2017 102 159 A1 describes a planar dynamic sound transducer, which often consists of two opposing magnet arrangements, each with several parallel magnet rods and a membrane fitted with a flat coil in between. The plane of the magnet arrangement is parallel to the plane of the membrane. The resulting repulsive forces between the two magnet arrangements, as well as connecting elements for securing the arrangement, can cause stresses, distortions, bending, etc. Conventionally, the membrane foil is fixed either directly to the magnet holder or to a separate component, e.g., a support frame. The mechanical stresses are transferred to the very thin, prestressed membrane foil, impairing its flatness and / or the homogeneity of the mechanical stress.In the present planar dynamic transducer comprising a first planar magnet assembly, a mounting element, a diaphragm with conductive tracks, and at least one diaphragm support frame, the diaphragm support frame is clamped between the magnet assembly and the mounting element. An elastic decoupling element is located between the diaphragm support frame and the first magnet assembly and / or between the diaphragm support frame and the mounting element.

[0032] US 2014 / 0270326 A1 describes a planar magnetic transducer comprising a frame and a primary magnet array structure of elongated magnets adjacent to, and air-gapped from, a first surface of a movable portion of a thin-film or thin-structure diaphragm with conductive traces incorporated into the diaphragm. An additional pair of magnetic sources is mounted on the frame outside the oscillatory region of the diaphragm and above the plane of the opposite, second surface of the diaphragm to amplify the magnetic energy near the second surface of the film diaphragm, without any magnet arrays being mounted directly in front of the second surface of the diaphragm's oscillatory region between the additional pair of magnetic sources.

[0033] As is known from relevant material data sheets, the typically used

[0034] Due to their high coercive field strength, which is associated with the desired high energy density, magnet rods made of neodymium (Nd2Fel4B) (this also applies to other designs such as rings, etc.) require a very high magnetic field strength H of, for example, 2,400 kA / m to be fully magnetized or polarized, or even to the saturation range. Such field strengths, even if only required in pulses, can only be generated by magnetizing devices (electromagnets in the form of solenoids or other coils) whose dimensions significantly exceed those of the component to be magnetized.

[0035] Combined with the requirement that the magnetic bars must be arranged with alternating polarity, this inevitably means that the magnetic bars must be individually magnetized prior to assembly. During assembly or positioning in an assembly fixture or injection molding tool, the magnetic bars are therefore in a magnetized state and, depending on their relative position to each other and to other ferromagnetic components or tools, exert significant mechanical repulsion or attraction forces. For example, the force between two magnetic bars made of the common neodymium alloy "N45," each measuring 2 x 4 x 40 mm, is approximately 40 N upon contact, and at a distance of 2 mm, it is already 10 N.

[0036] To partially address this problem, US 2005 / 036646 A1, Figs. 42 to 44 show support grids with pins or webs protruding perpendicular to the surface. These prevent lateral movement of the magnetic bars due to repulsion / attraction forces until the adhesive between the magnetic bars and the support grid has cured. In particular, there is a constant force of attraction between planar, adjacent, parallel magnetic bars, usually with alternating polarity, which must be counteracted in a suitable manner in order to maintain the desired position and spacing between the magnetic bars. As additional magnetic bars are brought closer, however, they exert forces of a different direction, lifting the already positioned bars out of this position or twisting them (particularly when they are resting on non-magnetic material), unless further measures for temporary fixation are taken.

[0037] A further problem is the extreme brittleness or fragility and the very low elasticity of the magnetic rods due to their powder metallurgical manufacturing process. In the event of an uncontrolled collision or other increased force, this frequently leads to the breakage and fragmentation of the magnetic rods, resulting in material waste and endangering people and equipment from ejected fragments or crushing injuries. All of the properties of the magnetic rods mentioned above result in considerable effort in their storage, removal, manipulation, positioning, and temporary fixation until they are finally secured in their final position, e.g., by clamping or bonding to a carrier element or by plastic overmolding.Additional effort and costs arise for state-of-the-art planar dynamic sound transducers due to the multi-part structure consisting of a support system for the magnetic rods, a support system for the membrane foil, electrical connections, mechanical interfaces to the housing and other components, a protective grille and a baffle or housing.

[0038] In WO 03 / 094571 A2, Figs. 15-27 to 15-29 and the associated description describe an assembly method in which magnetic rods (15-2704, 15-2904) are positioned in the cavity of an injection mold and secured there by spring pins (15-2900). How these potentially conflicting steps (positioning, securing, and subsequent closing of the injection mold) are to be carried out is not explained in detail, despite detailed manufacturing process descriptions elsewhere in WO 03 / 094571 A2. The necessity of securing described here further highlights the problem of magnetic attraction forces discussed above.

[0039] In addition, the cavity wall, which is not described in detail, could be made of ferromagnetic steel; the resulting attractive forces to the wall would then support the temporary fixation of the magnetic rods, but at the same time, during insertion, would pose the risk of material breakage of the magnetic rods due to excessively rapid impact with the cavity wall and would also make demolding of the assembly much more difficult, with the magnetic rods potentially being broken out of the plastic if they adhere more strongly (magnetically) to the cavity wall or the ejectors than to the adjacent plastic parts.

[0040] In the next step, the magnetic rods of WO 03 / 094571 A2 are assembled into an assembly by overmolding them with a suitable plastic, which permanently fixes their relative position and simultaneously forms an acoustically open support grid (15-2600). The magnetic rods also have internal slots (15-2800) that are filled with the plasticized plastic to achieve a positive fit. This again indicates that the bond between the plastic and the usually smooth (e.g., nickel-plated) and non-tempered surface of the magnetic rods is insufficient, comparable to the desired low adhesion between the plastic and the cavity wall.

[0041] The additional machining step required to create the slots in the brittle magnetic rods is generally very costly, due in part to the required slow machining speed and / or the increased scrap rate. The high relevance of the cost of machining the magnetic rods is also demonstrated by the statement in WO 03 / 094571 A2, according to which the alignment of the magnetic rods to the cavity wall shown in Fig. 15-29 is advantageous for compensating for larger thickness tolerances that may arise during the production of the magnetic rods in order to save costs. 6. Planar dynamic principle with magnetic disk

[0042] To simplify the design and the required manufacturing processes, planar dynamic sound transducers are known. These transducers utilize a grid or a perforated disc made of a coherent, hard magnetic material. While this incurs investment costs for a casting tool, it also simplifies assembly, as only a single, usually unmagnetized and thus easy-to-handle magnetic component is required. The magnetization step, which usually follows, ensures the reproducible relative and absolute positioning of the magnetic poles.

[0043] However, in the state of the art, this grid has exclusively magnetic functions, and therefore always requires a separate carrier that establishes the mechanical coupling to the other components.

[0044] JP 2008 113365 A shows such a sound transducer with a perforated magnetic disk (22a, 22b) held by support grids (24a, 24b). The sound transducer consists of seven components, plus components for electrical and mechanical contact.

[0045] US 3,674,946 A describes a planar dynamic sound transducer that uses an elastic, flat, prefabricated, and multipolarly magnetized magnetic material ("Plastiform," e.g., type 1037), which is perforated and cut to size by punching or similar means. This material is barium ferrite bonded to rubber and has a low energy product of only approximately 1.1 MGOe. This comparatively weak magnetic material was chosen because it is very easy to process, assemble, and adapt to the shape of a non-planar support grid, e.g., through magnetic attraction between the magnetic material and the support grid. However, the magnetic field thus provided to drive the sound transducer is considerably weaker than that of other materials available at the time of filing US 3,674,946 A, and considerably weaker again than that of current neodymium magnets, which have an energy product of up to 52 MGOe.Due to the high elasticity of the magnetic material, the use of supporting structures and other assembly components is essential.

[0046] In a later application by the same inventor (US 4,471,173 A), in addition to the aforementioned elastic magnetic material, more magnetically strong materials made of rare earths such as samarium cobalt are mentioned, as well as the production of a perforated magnetic disk by unspecified molding ("molded to the shape illustrated") or punching ("die cut"). This magnetic disk represents an alternative to the individual magnetic strips used in the other illustrations of US 4,471,173 A and thus also requires a separate carrier grid and other discrete components. Another variation of an acoustically opened magnetic disk is described in US 10,455,343 B2. The magnetic disk 14 shown there is manufactured in one piece, has exclusively magnetic functionality, and is supplemented by a carrier grid 16, a membrane carrier ring 12, and other components.Although the magnetic disk 14 can be made of any ferromagnetic material, the specification of a required or preferred energy product of the material between 34 and 45 MGOe limits the material selection to anisotropic, all-metallic rare-earth magnets, in particular sintered neodymium magnets (Nd2Fel4B), which are commercially available in material grades with energy products between 30 and 52 MGOe. The low geometric complexity of the magnetic disk, which enables production by mechanical processing of sintered neodymium material, as well as the homogeneous surface-normal magnetization evident in Fig. 1A and Fig. 4B, also point to this anisotropic material. The alternative magnet materials ferrite, AINiCo, plastic bonded neodymium (usually isotropic) and sintered samarium cobalt only achieve maximum values ​​of 5, 9, 12 and 14, respectively.33 MGOe and are therefore not very suitable for sound transducers according to US 10,455,343 B2.

[0047] US 3,898,598 A describes a dynamic electroacoustic transducer with two slotted discs of permanent magnets arranged parallel to each other at a distance to generate a plurality of aligned magnetic fields of alternating polarity in a gap between them. A main diaphragm with a flat coil is held flat by two auxiliary diaphragms sandwiched around it and arranged parallel to the discs in the gap, with the magnetic fields perpendicularly intersecting the various parts of the coil. Two annular elastic holders clamp the peripheral edges of the main and auxiliary diaphragms between them to impart the required rigidity to the main diaphragm. Alternatively, a tension ring can impart the required rigidity to the main diaphragm, which is attached to the annular elastic holder.

[0048] JP 2010-268045 A addresses the problem of providing a thin acoustic electromechanical transducer that can be assembled more easily than before and has an improved design. To this end, a planar loudspeaker is proposed, which is used as a thin acoustic electromechanical transducer. It includes a pair of covers as a housing, and four pins and the like are provided in the housing. The pins are held by fitting both ends into the fitting holes provided in the permanent magnet plates, function as a positioning tool for positioning a vibrating diaphragm and corresponding buffer members during assembly of the planar loudspeaker, and function as displacement control means for controlling a displacement direction of the vibrating diaphragm after assembly. Furthermore, the pin is incorporated into the housing, thereby maintaining the structure, including the flatness of the housing.The disadvantage, however, is that such planar dynamic sound transducers still consist of additional components.

[0049] Components such as contact terminals, membrane rings, spacer rings, screw connections and the like, which cause corresponding manufacturing effort, tolerance chains and costs.

[0050] For example, DE 10 2017 122660 A1 describes a planar dynamic sound transducer containing a magnetic plate with elongated air gaps arranged perpendicular to the conductor. The magnetic plate is magnetized with one side and multipoles, so that on the side facing the diaphragm and the conductor, it contains at least one north pole and one south pole along each air gap on both sides. This generates the strongest deflection force on the diaphragm directly below the magnetic rods, where the acoustic damping is also greatest. The width of the air gaps in the magnetic plate can also be freely selected because they are independent of the width or spacing of the conductor tracks.

[0051] Nevertheless, the numerous individual parts and assembly steps of planar dynamic sound transducers often result in corresponding manufacturing and assembly costs, a variety of materials that impedes repairability and recycling, including the frequent use of adhesives, and quality problems due to the successive tolerance chains of the individual components. This results in significant material and labor costs in the manufacture of this type of sound transducer, which hampers efficient production in high volumes and low unit costs.

[0052] An object of the present invention is to provide a planar dynamic sound transducer of the type described above, the manufacture and, in particular, assembly of which can be simplified. Additionally or alternatively, the acoustic and / or electrical properties are to be improved. This should be implemented as simply, cost-effectively, and with the least possible space and / or weight. At the very least, an alternative to known planar dynamic sound transducers is to be provided.

[0053] According to the invention, this object is achieved by a planar dynamic sound transducer, a magnet arrangement, a receiver, a microphone, and a loudspeaker having the features of the independent claims. Advantageous further developments are described in the subclaims.

[0054] Thus, the present invention relates to a planar dynamic sound transducer comprising at least one magnet arrangement with a plurality of magnetic poles and with at least one acoustic opening, and with a membrane with at least one conductor track. The magnet arrangement comprises an inner region having the magnetic poles and an edge region surrounding the inner region and connecting its elements to one another. The inner region of the magnet arrangement is offset perpendicularly to the horizontal relative to the conductor track of the membrane and arranged horizontally at least overlapping the conductor track of the membrane. Such planar dynamic sound transducers are known, for example, from US Pat. No. 3,674,946 A, as described above.

[0055] The planar dynamic sound transducer according to the invention is characterized in that the edge region of the magnet arrangement further has at least one mechanical, acoustic and / or electrical function of the planar dynamic sound transducer. A mechanical function can be understood as a mechanical connection and in particular a holding or fastening of the edge region of the magnet arrangement with in particular the membrane, which can occur directly or indirectly. A mechanical function can also be a spacing or a contact or a non-spacing perpendicular to the horizontal between the edge region of the magnet arrangement and the membrane. An acoustic function can be understood as influencing the acoustic sound generation or sound detection. An electrical function can be understood as electrical contacting, in particular of the conductor track of the membrane. Further mechanical, acoustic and / oror electrical function of the planar dynamic sound transducer, which is made possible by the edge area of ​​the magnet arrangement, are not excluded by this.

[0056] In any case, the mechanical, acoustic, and / or electrical properties of the planar dynamic sound transducer can be improved or enhanced, either individually or in combination, which can correspondingly improve the quality of the planar dynamic sound transducer and a corresponding product such as a handset, in particular a headset, a microphone, a loudspeaker, and the like. Additionally or alternatively, the manufacturing and, in particular, assembly costs can be reduced by having more functions performed by one component in the form of the magnet arrangement or its edge region, or by having the same functions performed by fewer components, thus eliminating the need for additional components that would have to be manufactured and assembled.Additionally or alternatively, certain design options, such as the electrical contacting of a filigree conductor track of the membrane by means of the magnet arrangement, as will be described in more detail below, can be made possible in the first place.

[0057] In any case, the edge region of the magnet arrangement can serve not only to connect or mechanically hold the interior region or its elements, such as its magnetic poles, as previously known, but the edge region of the magnet arrangement can also be designed according to the invention to be sufficiently large, particularly in the radial direction or horizontally, to enable additional mechanical, acoustic, and / or electrical functions and properties as described above. The design of the edge region of the magnet arrangement can be specifically designed to enable the corresponding function and, in particular, to be carried out as effectively as possible.

[0058] Preferably, arranging the inner area of ​​the magnet assembly perpendicular to the horizontal axis relative to the membrane's conductor track and horizontally congruent with the membrane's conductor track can increase the efficiency of the interaction between the magnetic poles of the magnet assembly and the membrane's conductor track. For this purpose, the acoustic opening of the magnet assembly can be aligned with the membrane's conductor track.

[0059] According to one aspect of the invention, the inner region of the magnet assembly and the edge region of the magnet assembly are formed integrally by a magnetic body, and at least the inner region of the magnet assembly comprises, preferably consists of, a hard magnetic material. A hard magnetic material is understood to be a permanently magnetic material, which thus has a constant magnetic field and maintains it permanently. Alloys of iron, cobalt, nickel, certain ferrites, or even rare earths, for example, can be used to form the hard magnetic inner region of the magnet body and thus the magnetic poles of the magnet assembly.

[0060] In other words, according to the invention, additional magnetic elements as separate components can be dispensed with, which were previously applied to a grid or the like in order to form a previously known magnet arrangement together with the grid. Rather, according to the invention, the magnet arrangement or its magnetic body can be designed both as a mechanically stable element, in particular with an edge region with additional mechanical, acoustic and / or electrical functions as described above, and as a permanent magnetic element in order to combine these properties and thus avoid at least two components at this point in the planar dynamic sound transducer. This can simplify assembly accordingly. It can also save weight and / or installation space, in particular in the direction perpendicular to the horizontal.

[0061] This can be achieved by providing at least the interior region of the magnet arrangement with a hard magnetic material in sufficient quantity to achieve the desired interaction with the conductor track, and additionally comprising an additional, preferably non-magnetic, material to complete the magnet arrangement or its interior region and to form the edge region of the magnet arrangement. This can potentially keep the manufacturing costs of the magnet arrangement low if the hard magnetic material is more expensive than the additional material. Alternatively, however, the magnet arrangement or its magnetic body can also consist entirely of the hard magnetic material, at least in the interior region, which can simplify manufacturing and possibly thus make it more cost-effective. This can preferably also apply to the edge region.

[0062] In any case, the magnet arrangement can be formed in one piece, i.e. integrally or monolithically, which can be done by milling, compression molding or punching, but also by primary forming such as injection molding, die casting, metal powder injection molding, 3D printing and the like. This can also make production more cost-effective, particularly when using only a single material. However, the one-piece production can also be done using at least two different materials in a two-component process, for example by injection molding, so that, as already mentioned, at least two different materials can be used in combination with one another. For example, the interior can, partially or completely, comprise a hard magnetic material orconsist of this, while the edge area can consist of a non-magnetic material, which can save hard magnetic material and thus keep the manufacturing costs of the magnet arrangement low.

[0063] It may be particularly preferable to design at least the interior region of the magnet arrangement and very particularly precisely or only the interior region of the magnet arrangement to be hard magnetic and preferably to use hard magnetic particles, for example made of neodymium-iron-boron, which are embedded in a plastic material such as polyamide, in particular polyamide 6 or 12. Arranging or concentrating the hard magnetic particles, for example by means of a two-component injection molding process, precisely or only in the interior region of the magnet arrangement can enable the use of such hard magnetic particles exactly where the magnetic field is required in order to keep the amount of hard magnetic material and thus the costs as low as possible or to minimize them. The edge region of the magnet arrangement can then be designed to be free of the hard magnetic material in order to save on the costs of the hard magnetic material there.

[0064] According to a further aspect of the invention, the edge region of the magnet arrangement is formed from a different material than the inner region of the magnet arrangement, preferably from a material with a lower specific gravity and / or from a material with less or no magnetization and / or from an elastic material. This allows the corresponding aspects described above and below to be implemented in concrete terms.

[0065] According to a further aspect of the invention, the inner region of the magnet arrangement was formed from a first material in a first process step and the edge region of the magnet arrangement was formed from a second, different material in a second process step. This can be done, for example, as a two-component injection molding process (2K injection molding). The names of the first and second materials are not to be understood in the order of use. For example, in the first sub-step of an overall injection molding process, a structural grid is formed from the non-magnetic or weakly magnetic material component. This structural grid, through its shape and material properties such as admixed short glass or carbon fibers, corresponds to the expected mechanical loads and has the desired acoustic properties such as transparency or acoustic resistance.

[0066] After the grid has sufficiently solidified, a sub-element of the injection mold is moved in the second step to create a new cavity in the interior, which largely corresponds to the grid structure in the horizontal plane and is located on the side of the previously produced grid facing the membrane. This new cavity can now be filled with the magnetic material component, forming a comparatively thin layer on the previously produced grid and bonding it to it through its surface plasticization.

[0067] In this way, the thickness and thus the amount of the required magnetic material component is reduced to the minimum required for magnetic field generation. Since the strength of the magnetizing field in single-sided multipolar magnetization decreases exponentially with the distance from the flat magnetizing device, a material thickness of, for example, 30% of the magnetic pole spacing is sufficient. With a pole spacing (between the center lines of adjacent north and south pole strips) of 5 mm, the thickness of the magnetic material component can be 1.5 mm.The edge region and other associated elements (such as walls for forming acoustic channels or a loudspeaker enclosure), which must meet lower mechanical requirements and which are manufactured within the framework of the same overall injection molding process, can be produced together with the structural lattice in the first sub-step from the same non- or weakly magnetic material component, or they can be produced in a third sub-step from a third material component, which, for example, consists only of the polymer matrix without any admixtures.

[0068] In a third or fourth sub-step, after moving individual tool elements, a sub-area made of an elastic material can be added, for example a circumferential sealing ring or elements for vibration decoupling, whereby a material-to-material connection between the elastic material and the adjacent, already manufactured sub-area is achieved through suitable material selection or material pairing and suitable process parameters.

[0069] If possible surrounding or adjacent components such as housing parts or cladding were not manufactured in one of the sub-steps described above, these can also consist of fiber composite materials, pressed fiber material, foamed plastic or metal, or similar materials, which are placed in a corresponding tool cavity and are fully or partially penetrated by the melt mass introduced in another sub-step, or are bonded to it in the boundary area by surface plasticization.

[0070] The selection and sequence of the described sub-steps can be adapted to the specific design, material selection and other requirements without deviating from the basic idea of ​​the invention.

[0071] All of the previously described configurations of the magnetic grid according to the invention can also be manufactured using other manufacturing processes, in particular using additive manufacturing processes such as 3D printing, laser sintering, stereolithography, etc., or using powder metallurgical processes such as laser melting, metal powder injection molding, etc., without deviating from the basic idea of ​​the invention. Additional components, such as a housing rear panel (which forms a hollow body and thus cannot be manufactured as a whole in a single injection molding process), can be manufactured in the same printing process. Likewise, for the assembly or integration of the sound transducer according to the invention into larger assemblies, structures, devices, housings, vehicles, etc.All common joining techniques such as screw connections, snap-fit ​​connections, welding, soldering, gluing, shrink-fitting, but also overmolding and similar processes can be used without deviating from the basic idea of ​​the invention.

[0072] According to a further aspect of the invention, the edge region, preferably and sections of the inner region, of the magnet arrangement are formed from a first material in a first process step, and the, preferably remaining, inner region of the magnet arrangement is then formed from a second, different material in a second process step. Preferably, in a first process step, the edge region of the magnet arrangement and preferably parts of the inner region, in particular webs, as an inward extension of the edge region, are formed from a first, slightly or non-magnetic, and mechanically comparatively stiff and / or strong material, and in a further process step, further parts of the inner region of the magnet arrangement, in particular webs, are formed from a second material with hard magnetic properties. This can represent an alternative implementation option.

[0073] According to a further aspect of the invention, the edge region comprises an elastic material at least in sections. Preferably, in a third method step, the edge region was formed in sections from a third, different elastic material. Preferably, in a further, preferably third method step, the edge region of the magnet arrangement was supplemented by one or more subregions made of preferably elastic material. This allows the edge region to be formed elastically at least partially or in sections. This can be achieved within the framework of the multi-stage manufacturing process, in particular the injection molding process, by using an appropriate material.

[0074] According to a further aspect of the invention, the edge region of the magnet arrangement is designed to be higher perpendicular to the horizontal than the inner region of the magnet arrangement. The membrane can therefore lie directly against the edge region of the magnet arrangement perpendicular to the horizontal and can be connected to it by gluing, ultrasonic welding, clamping or other joining methods. In this way, a distance perpendicular to the horizontal between the magnetic poles of the inner region of the magnet arrangement and the conductor track of the membrane, which distance is necessary or usual for the oscillation ability of the membrane and thus for sound generation, can be created by the edge region of the magnet arrangement itself. Accordingly, an additional component as a receiving element or support element can be dispensed with, which can reduce manufacturing costs. Until now, this would have required an additional element or component which served as a support element, as a receiving element orAs a support element, it serves to support, accommodate, or carry, e.g., by gluing, the membrane or membrane film, whose function can additionally be assumed by the raised edge area of ​​the magnet arrangement, according to the invention. This could also be an element or component that, as a "loose" element without connection or gluing, creates the distance perpendicular to the horizontal between the magnet arrangement and the membrane, so that its function can also additionally be assumed by the raised edge area of ​​the magnet arrangement, according to the invention.

[0075] If the membrane is arranged perpendicular to the horizontal between the magnet arrangement and a protective grid, a spacer element can be arranged between the membrane and the protective grid as a separate element, component, or part to achieve a suitable distance for the vibrational deflection of the membrane. Alternatively, the edge area of ​​the protective grid can also be raised perpendicular to the horizontal, pointing towards the membrane, as described above with regard to the edge area of ​​the magnet arrangement, in order to achieve the required distance even without an additional spacer element as a separate element, component, or part.

[0076] According to a further aspect of the invention, the conductor track of the membrane is electrically conductively connected at at least one conductor track end, preferably at both conductor track ends, to a contact element of the edge region of the magnet arrangement, and the magnet arrangement, preferably the edge region of the magnet arrangement, preferably has in each case an outer contact element which is designed to be electrically conductively contacted, preferably soldered, from outside the magnet arrangement. In this way, electrical contact can be made with the usually very delicate membrane or its conductor track by means of corresponding electrically conductive contacts in the magnet arrangement, which itself is usually significantly more massive and stable than the membrane. This can, on the one hand, make the comparatively thin orThe delicate design of the membrane and, on the other hand, still allow electrical contact with the membrane's conductor track, for example, through comparatively solid electrical contact elements and, in particular, solder joints. For this purpose, the magnet arrangement can serve as an electrical bridge between the membrane's conductor track and the connecting elements or solder joints that can be electrically contacted from outside the planar dynamic sound transducer. The electrically conductive connection between the end of the conductor track or both ends of the conductor track can be achieved, in particular, via contact surfaces and, if necessary, additional electrically conductive adhesive at this point.

[0077] According to a further aspect of the invention, the planar dynamic sound transducer comprises at least one support element, which is arranged perpendicular to the horizontal between the edge region of the magnet arrangement and the membrane and spaced the inner region of the magnet arrangement from the membrane by means of a hollow inner region. This alternatively allows a required or usual distance perpendicular to the horizontal between the magnetic poles of the inner region of the magnet arrangement and the conductor track of the membrane to be established. Although this requires an additional component as a support element or as a receiving element, the design of the magnet arrangement can be simplified.

[0078] According to a further aspect of the invention, the conductor track of the membrane is electrically conductively connected to a contact element of the support element at at least one conductor track end, preferably at both conductor track ends, and the support element preferably has an outer contact element which is designed to be electrically conductively contacted, preferably soldered, from outside the magnet arrangement. As a result, the properties and advantages described above can be implemented alternatively if a support element is provided perpendicular to the horizontal in order to achieve the necessary distance perpendicular to the horizontal between the magnetic poles of the magnet arrangement and the conductor track of the membrane, without structuring the magnet arrangement with a raised edge.This can also enable the implementation of the previously described aspect of electrical contacting in this case as described above, whereby the electrical contacting can then be made from outside the planar dynamic sound transducer to the support element.

[0079] According to a further aspect of the invention, the acoustic opening of the magnet arrangement follows the course of the conductor track of the membrane at least substantially, preferably completely. In other words, the acoustic opening of the magnet arrangement and the conductor track of the membrane overlap at least substantially, preferably completely, viewed in a direction perpendicular to the horizontal. In this way, unequal magnetic poles are provided on both sides of each conductor track section and parallel thereto. The field lines running between these magnetic poles are optimally aligned tangentially to the conductor track by this arrangement and have a virtually constant density over the entire length of the conductor track. As a result, the magnetic material used can be optimally utilized and a driving force that is particularly evenly distributed across the membrane surface can be achieved.

[0080] According to a further aspect of the invention, the acoustic opening of the magnet arrangement and the conductor track of the membrane extend essentially elongately and parallel to one another in the direction of the greatest extent of the magnet arrangement. For this purpose, at least the acoustic opening of the magnet arrangement and the conductor track of the membrane can be rectangular or oval with an elongated extension in the horizontal direction. The rectangular or oval design represents preferred options for the overall shape of the magnet arrangement and thus also of the entire planar dynamic sound transducer in order to implement a preferred or greatest extension. In any case, the number of parallel conductor track segments and the number of connecting pieces (turns) can be kept low, which can simplify the manufacture of the magnet arrangement.This also makes it possible to keep the number of sections of the conductor track, which contribute comparatively little to the drive of the planar dynamic sound transducer near the edge area of ​​the magnet arrangement, but increase the length of the conductor track and thus its electrical resistance, low, since with the length of the conductor track and thus also with the increased value of the electrical resistance of the conductor track, the electrical current intensity and thus the driving force can decrease during operation.

[0081] According to a further aspect of the invention, the edge region of the magnet arrangement has at least one guide pin, preferably a pair of guide pins, and the membrane, preferably and a support element and / or a spacer element and / or a protective grid, at least one through-opening, preferably a pair of through-openings, for the guide pin of the magnet arrangement. This also allows the edge region of the magnet arrangement to assume an additional mechanical function and, by means of the guide pins, to facilitate assembly and to improve the fit or matching of the magnet arrangement and membrane, and optionally also other elements or components of the planar dynamic sound transducer, in that the membrane and optionally other elements, components or parts can be placed on the guide pin(s) and thus guided and arranged in a defined manner relative to the magnet arrangement.This can be achieved in particular using a pair of guide pins. However, more than just two guide pins can also be used, which can improve guidance despite increased effort. Preferably, the ends of the guide pins can be reshaped by applying force and / or heat after assembly of the diaphragm or the other sound transducer components in order to fix the diaphragm or the other components. This can ensure permanent hold and, at the same time, be simple and cost-effective. This can be achieved more effectively the more guide pins are used, although the number of guide pins should, on the other hand, be limited to keep effort to a minimum. For example, the use of four to eight guide pins can represent a compromise between effort and effectiveness.

[0082] In any case, when using multiple guide pins, it is advantageous to distribute them as evenly as possible along the circumferential direction of the planar dynamic transducer. This can benefit both guidance and retention.

[0083] Alternatively, if the membrane is arranged perpendicular to the horizontal between the magnet assembly and a protective grid, this can also be implemented in such a way that the guide pin(s) are arranged at the edge of the protective grid and, in particular, are formed integrally there, and the edge region of the magnet assembly has one or more corresponding through-openings. This allows the same effect to be achieved with the same technical means, which simply need to be arranged in reverse with regard to the magnet assembly and the protective grid.

[0084] According to a further aspect of the invention, the edge region of the magnet arrangement has at least one receptacle, preferably a plurality of receptacles, for receiving a fastening means, preferably a screw, and the membrane, preferably a support element and / or a spacer element and / or a protective grid, has at least one through-opening, preferably a plurality of through-openings, for the fastening means. This can enable a corresponding mechanically simple and durable connection. For this purpose, screws can in particular be used, which can be removed particularly easily and non-destructively in order to replace elements or to repair the planar dynamic sound transducer or to separate its individual parts and feed them into the material cycle (recycling). For this purpose, such a receptacle can also be formed as an internal thread or provided with a threaded insert.

[0085] According to a further aspect of the invention, the edge region of the magnet arrangement has at least one snap hook, preferably a plurality of snap hooks, for gripping the membrane, preferably a spacer element or a protective grid, wherein a snap hook head facing away from the magnet arrangement is preferably magnetic. In other words, this allows a snap, locking, or clamping connection to be provided for holding and positioning the elements or components of the planar dynamic sound transducer, which can alternatively be implemented simply and cost-effectively. In particular, this allows the holding function to be combined with the positioning function in one element or in one step, which can be particularly simple and cost-effective.

[0086] Preferably, the snap hook can be magnetically configured, particularly at its upper end perpendicular to the horizontal, to magnetically attach additional components, such as ear pads of a headset. This can enable additional functions in a simple, cost-effective, and / or space-saving manner.

[0087] 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, which is open, preferably to at least one acoustic opening, particularly preferably to a plurality of acoustic openings, wherein the length of the cavity and / or the distance between two openings of the cavity is selected such that at least one sound frequency, the wavelength of which is in a predetermined ratio to the length of the cavity and / or to the distance between two openings of the cavity, experiences a resonance and / or a reflection.

[0088] According to a further aspect of the invention, the interior region, preferably at least one magnetic web, particularly preferably a plurality of magnetic webs, very particularly preferably all of the magnetic webs, of the interior space, has at least one, preferably horizontal, cavity, preferably a plurality of, preferably horizontal, cavities, which is open, preferably to at least one acoustic opening, particularly preferably to a plurality of acoustic openings, wherein the length of the cavity and / or the distance between two openings of the cavity is selected such that at least one sound frequency, the wavelength of which is in a predetermined ratio to the length of the cavity and / or to the distance between two openings of the cavity, experiences resonance and / or reflection.

[0089] This means that cavities can be created in the interior and / or edge areas of the magnet arrangement, preferably horizontally and / or parallel to the greatest extent of the magnet arrangement, e.g. by sliders in an injection molding tool, by mechanical post-processing, or by appropriate additive forming such as laser sintering, 3D printing, etc. These cavities can be provided with openings at selected positions through which sound flow can enter and exit. At certain sound frequencies, whose wavelength is in a specific ratio to the cavity length or the opening spacing, resonances and / or reflections can arise that can overlap with the regular sound radiation of the planar dynamic sound transducer. This overlap can be constructive or destructive depending on the phase position of the resonances and / or reflections.Thus, at these frequencies, the sound emitted to the outside can be amplified or weakened.

[0090] This allows an acoustically effective shape of the magnet arrangement to be achieved. This can be achieved using just the edge area of ​​the magnet arrangement or just the inside of the magnet arrangement. However, both areas of the magnet arrangement can also be used in combination. In any case, the design can be for the greatest possible absorption and destructive interference in order to minimize the sound emitted to the outside. Alternatively, the design can also be made in such a way that, for example, in headphones with a closed housing, unwanted reflections and standing waves through the rear wall of the housing can be reduced. Alternatively, for example, high frequencies that are radiated by the diaphragm with reduced sound pressure due to its mass inhibition can be amplified by resonator effects, thus creating a uniform, linear sound impression up to high frequencies.

[0091] According to a further aspect of the invention, the interior region is designed to be more acoustically transparent in some sections, particularly for high sound frequencies, and less acoustically transparent in the rest, particularly for high sound frequencies. In other words, this relates to the structure of the interior region and provides for a shape of the open regions in a partial region of the interior region such that this is accompanied by acoustic transparency, particularly also for high sound frequencies, while in the remaining region of the grille the open regions are shaped such that they are acoustically less permeable or not at all, particularly for high sound frequencies. This results in a reduced size of the sound opening, which leads to a reduction in the directivity of the sound radiation, which is determined by the relationship between the size of the outward-radiating surface and the signal frequency.

[0092] According to a further aspect of the invention, the planar dynamic sound transducer comprises a mirror-symmetric pair of magnet arrangements surrounding the diaphragm perpendicular to the horizontal. This allows for the magnet arrangements to be arranged on both sides of the diaphragm, which can expand the design possibilities of the planar dynamic sound transducer. Implementing this using two mirror-symmetric magnet arrangements that are identical and match each other can enable the dual use of the same component and thus keep manufacturing costs low.

[0093] In other words, both magnet arrangements can preferably be configured largely identically and symmetrically along a main axis. Both magnet arrangements can preferably be mechanically reinforced by their shape and / or by embedding or connecting stiffening elements. According to a further aspect of the invention, the magnet arrangement has at least one further inner region, which has magnetic poles and is surrounded by the edge region.

[0094] In other words, the edge region is shaped in such a way that it has one or more additional inner regions with magnetic material and an optional receptacle for a membrane foil with conductor tracks. These additional inner regions can be located next to the first inner region or completely or partially surround it. These inner regions can be operated as additional independent sound transducers by attaching a membrane foil with contacted conductor tracks. These can differ from each other and / or from the first sound transducer, for example, in size, grid structure, membrane excursion, etc. and are therefore suitable, for example, for the reproduction of different frequency ranges. For this purpose, the various sound transducers can be excited with their own electrical signals, which only contain the relevant signal frequencies. These signals can, for example,generated by digital signal processing and subsequent digital-to-analog conversion and amplification, or by passive components such as capacitors or passive filter networks.

[0095] An advantage is that the individual transducers can be dimensioned and optimized for the reproduction of their respective frequency ranges. For example, low signal frequencies typically require significantly larger diaphragm surfaces and diaphragm excursions, while high signal frequencies can be delivered through a lightweight and small-area diaphragm. This also avoids a sharp increase in the directivity of the sound radiation towards high frequencies.

[0096] Particularly small versions of the first or an additional grid area and the associated membrane are also suitable for use as an electrodynamic microphone.

[0097] The various sound transducers mentioned above can also be similar or identical in shape and be excited with different digital-to-analog converted and amplified signals, e.g., generated by digital signal processing such as beamforming or wave field synthesis, to achieve, for example, a controllable directivity of the sound radiation or the simulation of arbitrarily shaped acoustic wavefronts. In this way, a locally limited sound reinforcement or a virtual acoustic environment can be created.

[0098] According to a further aspect of the invention, the magnet arrangement has at least one further inner region which is free of magnetic poles and is surrounded by the edge region. The further inner region can also be referred to as the second inner region, to distinguish it from the previously considered sole inner region as the first inner region. In other words, the edge region is shaped such that it has one or more additional inner regions without magnetic material and with an optional receptacle for a membrane film. These additional inner regions can be located next to the first inner region or surround it completely or partially. These inner regions can be operated as so-called passive radiators by attaching a membrane film. These can differ from one another and / or from the first sound transducer, e.g. in terms of size, grid structure, membrane excursion, etc.differ and, in conjunction with the coupled air volumes, have corresponding first-order resonance frequencies. In order to adjust this resonance frequency and, for example, achieve a desired low value, the prestress and the mass of the membrane film can be varied, e.g. by varying the film thickness or by mechanical structuring (corrugation, embossing, etc.) of the membrane film or by additional mass-bearing materials that are permanently bonded to the membrane film, for example by gluing, laminating, overmolding, or similar. The passive radiator(s) can be strongly acoustically coupled to the active sound transducer(s) at the rear by shared air volumes separated from the environment, so that they are excited by these to resonate at certain signal frequencies, which is accompanied by a phase shift.The result is an additional sound radiation of certain frequencies, which predominantly constructively overlaps with the sound radiation of the active transducer(s) and thus increases the total emitted sound energy at these frequencies, for example in the bass range.

[0099] According to a further aspect of the invention, the edge region of the magnet arrangement has at least one additional wall, which runs essentially outside the horizontal and acoustically separates the inner region of the magnet arrangement from the further inner region. The additional second wall can, in particular, run essentially exactly perpendicular to the horizontal or extend away from the edge region, which can be considered to run horizontally. In any case, a structural and / or acoustic separation can be achieved by means of the additional wall.

[0100] According to a further aspect of the invention, the edge region of the magnet arrangement is designed as a baffle.

[0101] In other words, the edge area is shaped to function as a baffle, i.e., it largely prevents an acoustic short circuit between the front and back of the membrane in the relevant frequency range and thus improves the reproduction of low audio frequencies (e.g., bass tones). For this purpose, the edge area can be enlarged to such an extent that a sufficiently long detour is created for the sound generated at the rear, so that at the desired sound reception location, at the lowest relevant signal frequency, it only interferes with the sound generated at the front with minimal destructive effect, i.e., the phase difference between these two sound waves is reduced from the original 180° to less than 140° (a maximum of around 3dB amplitude reduction due to destructive interference). Additional functional features such as recesses, holes, hooks, bolts, webs, etc. can be created in the same manufacturing process.assembly with, and spacing from, other components and structures.

[0102] Alternatively, the edge area can also be shaped to form the front and / or side walls of a loudspeaker cabinet and incorporate features such as holes, threads, snap hooks, etc. for attaching one or more components that form the side and / or rear walls. In this way, a fully or partially enclosed loudspeaker cabinet can be created. This prevents or reduces acoustic short circuits, even with dimensions significantly smaller than those required for the aforementioned baffle.

[0103] In the interests of efficient and integrated production, the edge area extended to form the baffle or loudspeaker housing part can also be incorporated into other components such as a flat housing, body or panel component such as a housing part of a screen or a lamp, an outer surface of a piece of furniture or a ceiling suspension, or an interior panel of an automobile and can be manufactured wholly or partly together with it in the same injection molding process.

[0104] Additionally, the edge region can have additional walls, preferably extending substantially perpendicular to the membrane plane, between the drive region and the outer edge of the edge region. These additional walls, optionally in conjunction with the separate rear wall, can form an acoustic channel of defined length that conducts sound energy from the rear of the membrane to a sound outlet located in one of the outer housing walls. Thus, depending on the length and cross-sectional area of ​​the channel, an acoustic detour is formed, similar to that of the baffle described above, but with significantly smaller dimensions than those required for the aforementioned baffle.

[0105] Or a resonance system is formed, consisting of the air in the duct (moving mass) and the air outside the duct in the closed housing (acoustic spring), which causes an increased sound radiation at the resonance frequency.

[0106] The acoustic channel can be constant or variable over its length in terms of shape and / or area of ​​the cross-section, and it can have a straight, curved or angled course; accordingly, for example, a horn, an inverted horn, or a so-called

[0107] A transmission line is formed. These additional walls can also, if necessary in conjunction with the separate rear wall, divide the enclosure volume, for example, to provide each transducer with an independent air volume when more than one active transducer is present.

[0108] According to a further aspect of the invention, the edge region of the magnet arrangement has at least one wall extending substantially outside the horizontal plane, which at least partially encloses at least one interior region. In other words, parts of the edge region of the magnet arrangement can be designed as one or more walls extending substantially outside the horizontal plane, which partially or completely enclose at least one interior region. Optionally, this wall can also be designed as a rear wall of a housing, connected, for example, by a film hinge.

[0109] This allows a wall or partition to be formed for lateral delimitation, preferably integral with the edge area, which can increase design flexibility. This can also increase the stability of the magnet arrangement.

[0110] According to a further aspect of the invention, the magnet arrangement, together with a rear wall, forms a housing for the planar dynamic sound transducer. This allows for the creation of a housed or enclosed space.

[0111] Preferably, providing the rear wall, preferably by a film hinge, connected to the wall of the edge region of the magnet arrangement, preferably formed in one piece, can simplify assembly and manufacture.

[0112] According to a further aspect of the invention, the edge region of the magnet arrangement has at least one wall extending substantially outside the horizontal, which forms at least one acoustic channel configured to acoustically communicate with the air volume above the interior region and with the surrounding atmosphere. In other words, the edge region of the magnet arrangement has one or more additional walls extending substantially outside the horizontal and forming one or more acoustic channels that acoustically communicate with the air volume above the interior region or with the air volume above one or more optional additional interior regions and with the surrounding atmosphere. This can increase the design options.

[0113] According to a further aspect of the invention, the edge region of the magnet arrangement has at least one surface element, preferably extending substantially horizontally, preferably formed in one piece. In other words, the edge region of the magnet arrangement can have one or more further surface elements, which are suitable for assembly or integration into larger TI

[0114] assemblies, devices or vehicles. This can be the assembly of the planar dynamic

[0115] sound transducer.

[0116] The present invention also relates to a magnet arrangement for use in a planar dynamic sound transducer as described above. This allows a magnet arrangement to be provided as a component or as an assembly in order to implement a planar dynamic sound transducer according to the invention as described above and to utilize its properties and advantages.

[0117] The present invention also relates to an earpiece, preferably a headphone, with at least one planar dynamic sound transducer as described above. This allows the properties and advantages of a planar dynamic sound transducer according to the invention, as described above, to be implemented and utilized in an earpiece, and in particular in a headphone.

[0118] The present invention also relates to a microphone with at least one planar dynamic sound transducer as described above. This allows the properties and advantages of a planar dynamic sound transducer according to the invention, as described above, to be implemented and utilized in a microphone.

[0119] The present invention also relates to a loudspeaker with at least one planar dynamic sound transducer as described above. This allows the properties and advantages of a planar dynamic sound transducer according to the invention, as described above, to be implemented and utilized in a loudspeaker.

[0120] The present invention relates to a loudspeaker-microphone combination with at least one planar dynamic sound transducer as described above, wherein at least the inner region with an associated first diaphragm is configured as a loudspeaker and at least the further inner region with an associated further diaphragm is configured as a microphone. This can represent an advantageous possibility for implementing or utilizing the corresponding properties and advantages.

[0121] In other words, the present invention relates to a magnet arrangement, which can also be referred to as a magnetic grid or a magnet system. The magnet arrangement can be manufactured with suitable sound passage openings from a single piece (monolithic), e.g. by milling, injection molding, die casting, metal powder injection molding, compression molding, 3D printing, or similar, and from a suitable material such as a plastic matrix (e.g. polyamide 6 or 12), which can be filled at least or precisely in the interior with hard magnetic particles such as neodymium-iron-boron. The filling level of the hard magnetic particles in the surrounding material can be as high as possible for a high efficiency of the sound transducer, but can be adapted depending on the requirements of the part geometry and the manufacturing process.When using anisotropic particles, a suitable magnetic field can be applied during the primary forming process or in a subsequent step to mechanically align the magnetic particles, e.g. by means of permanent magnets or electromagnets in the injection molding tool.

[0122] Aspects of the invention may in particular be the following, in addition or alternatively to each other:

[0123] A planar dynamic sound transducer with a multi-pole magnetized grid made of material containing hard magnetic material, essentially consisting of one to four individual parts, as well as a substantially flat membrane film positioned essentially parallel and in direct proximity to the grid, with conductive tracks thereon, which generate a substantially surface-normal force when current flows through interaction with the magnetic field of the grid, wherein the magnetic grid has additional specific properties or shapes and / or elements or features that go beyond the provision of the magnetic field directly required for sound generation and that are beneficial to the performance, quality and / or assembly of the sound transducer and / or the product.

[0124] The special feature of this aspect of the invention can be seen in the design and structure of the magnetic grid to improve its properties and / or performance as a sound transducer or to increase its functionality in order to achieve greater utility, better quality, and lower costs. Specific features are explained below.

[0125] The magnet arrangement or the magnetic grid can have additional mechanical and / or magnetic features such as assembly holes, pins, recesses, snap hooks, spacer steps, support steps, magnetic poles outside the movable membrane surface, etc., which can enable the positioning, alignment, spacing and / or attachment of further components or elements such as a membrane film, a protective grille, an acoustic damping material, a housing, an ear cushion, a second mirrored magnetic grid, etc.

[0126] The planar dynamic sound transducer and the associated product can therefore, as generally described above, have further components in addition to the magnetic grid, which can or must be positioned and fixed relative to one another. The magnetic grid can have various elements or features that facilitate these purposes or replace some components or aids. Examples of this are: a. Guide pins: These can be made of the same base material as the magnetic grid and thus form a natural unit with it, i.e. be formed integrally with one another, or they can be firmly connected to the magnetic grid during production, e.g. by injection molding or 3D printing, for example by placing them as an insert in the mold and being over-molded with the moldable magnetic material, thus forming a solid unit with it.One or more such pins can make it possible to "thread" or position the other components using corresponding holes or recesses. Conversely, such pins can also be connected to another component and inserted into corresponding holes in the magnetic grid. A combination is also possible, e.g. the magnetic grid can have a guide pin on one side and a hole on the symmetrically opposite side; now a second similar magnetic grid, rotated by 180°, can be connected to the first magnetic grid and aligned via both pins to create a symmetrical drive system with two opposing magnetic grids. b.Snap hooks: These can be barbs that are slightly deformed during assembly in order to spring back into their original shape behind the joining partner and create a positive connection that fixes the components and does not require any further work steps or aids such as adhesives, screws, rivets or similar. At the same time, snap hooks can also have a guiding and alignment function, like the guide pins under point a. During the primary forming of the magnetic grid, snap hooks and similar functions can be formed from the base material and form a natural unit with the magnetic grid, or separate hooks made of spring steel, for example, can be used and connected to the magnetic grid during the primary forming process (e.g. overmolded). c. Distance and support steps: Some components, such as the membrane film, can be positioned and fixed at a defined distance from the magnetic grid.For this purpose, the magnetic grid can have a circumferential step of appropriate height to create this distance, and which can optionally also be the direct carrier of the membrane film, with the membrane film being attached to the circumferential step by gluing, clamping or other methods. Similar things can be done for other components such as protective grilles, dust protection, seals, acoustic damping elements, etc. d. Holes: If the various components are to be connected to one another or to a housing or similar using screws, a holding frame can be used in conventional construction which accommodates the magnet arrangement and has holes. According to the invention, the magnetic grid can contain these holes, which can be either through holes for screws or threaded holes (if necessary with threaded inserts or press-in nuts) for metric or self-tapping screws. In this way, additional work, tolerance risks and costs can be reduced or eliminated.which can be associated with the conventional assembly of, for example, ten magnetic bars and a holding frame. e. Additional magnetic poles: Due to the manufacturing method used here for the magnetic grid, hard magnetic material is also available outside the actual drive area (near the conductor tracks) and can be magnetized if required. These additional magnetic poles can be used to attract other permanent magnets, electromagnets or ferromagnetic components and thus to position and fix them. Examples of this are protective grilles made of steel or ear cushions with integrated support rings made of steel or integrated individual magnets. These components can be removed and reattached without tools or auxiliary materials, which can be particularly advantageous for the end user. These magnetic poles do not have to be at the level of the drive area, but can also be located on raised areas, such asthe top of the snap hooks or guide pins or the outside of the magnetic grid to enable this functionality where it is needed.

[0127] The magnet arrangement or the magnetic grid can have the same functionality as before, but with reduced overall weight and / or cost, by using lighter and / or less expensive materials or elements that are firmly connected to the magnetic grid or enclosed by it and can thus locally replace the hard magnetic material.

[0128] This aspect of the invention is based on the recognition that hard magnetic material such as neodymium-iron-boron has a relatively high density and is typically associated with relatively high raw material costs. Therefore, in areas that do not require magnetic functionality, this material can be replaced by other materials that have lower costs and / or lower densities. If the hard magnetic material is used as a filler in a plastic matrix, the same type of plastic, but without the filler, can be used, particularly in the non-magnetic areas, thus enabling a good, integral bond between the areas. However, other plastics, foamed materials, wood, and many others are also suitable.The non-magnetic areas, if they are in the plastic state, can either be printed or injection-molded together with the other areas using 2K manufacturing, or they can be manufactured upstream and placed as an insert in the casting mold or on the printing mold and integrated into the primary forming of the hard magnetic area and firmly connected to it.

[0129] The magnet arrangement or the magnetic grid can have features and / or integrated elements for the electrical contacting of the conductor tracks on the membrane film, e.g. contact surfaces, soldering surfaces, bonding pads, soldering lugs, etc. This aspect of the invention is based on the realization that the electrical contact between the conductor track and the supply lines can be challenging, since the conductor track and membrane film can in many cases be very thin and temperature-sensitive, so that soldering or bonding may not be possible. One solution according to the invention can consist of pressing flat metallic parts onto the ends of the conductor track, optionally combined with a conductive adhesive. These contact parts or the open ends of the conductor tracks, if appropriately flat and / or thick, can themselves allow a soldered connection to the supply lines and can, for example,They can be integrated into the magnetic grid as inserts to enable stable and easy-to-establish contact. This contacting method can be particularly advantageous when dealing with a symmetrical sound transducer as described above, which consists only of two magnetic grids and the diaphragm with a conductive track. If necessary, some surfaces of the contact parts can be electrically insulated, e.g., by coating, to prevent electrical shunting through the magnetic material.

[0130] The magnet arrangement or the magnetic grid can be mechanically reinforced and / or stiffened by its shape and / or by elements that are firmly connected to the magnet arrangement or the magnetic grid or enclosed by it in order to achieve greater robustness for demanding applications and / or to be able to permanently bear the repulsive forces in a symmetrical structure consisting of two magnetic grids arranged in mirror image and in close proximity to one another.

[0131] This means that the magnet arrangement or magnetic grid for the core functionality of providing a magnetic field in the drive area can be made relatively thin, e.g. around 1 mm thick. In this design, however, the stability and / or strength of the magnet arrangement or magnetic grid can be compromised, as the hard magnetic material can be brittle and fragile, particularly when significant forces act on the magnet arrangement or magnetic grid. Dynamic forces can arise during use due to collisions or falling, while static forces can arise, particularly in the case of a symmetrical structure consisting of two magnetic grids that repel each other. To increase the stability of the magnet arrangement or magnetic grid, it can be reinforced by suitable structural stiffeners, bracing, etc. Alternatively or additionally, other parts or materials can be incorporated into the magnet arrangement or magnetic grid.be integrated into the magnetic grid, e.g. inserts, 2K injection molding, carbon fibers, steel rods, metal sheets, etc.

[0132] The magnet arrangement or the magnet grid can be substantially symmetrical to at least one

[0133] The axis can be configured to enable the use of a second, similar magnetic grid for a symmetrical structure consisting of two mirrored magnetic grids. For a symmetrical structure consisting of two opposing magnetic grids, it can be advantageous if the same magnetic grid can be used twice. To enable the required 180° rotation, it can be advantageous for the magnetic grid to have at least one axis of symmetry, apart from individual features as described above.

[0134] The magnet arrangement or the magnetic grid can have acoustic properties that influence the sound field, the sound pressure, the sound velocity or the sound flow in the environment of the sound transducer or shape it in a frequency- or amplitude-dependent manner or influence the vibration behavior of the membrane foil or other elements in order to reduce or deliberately shape non-linear distortions or frequency-dependent amplitude fluctuations in the generated sound signal.

[0135] The magnet arrangement or the magnetic grid can be designed for complete acoustic transparency in its grid structure, i.e. the degree of opening and / or the shape of the openings it contains. Alternatively, it can also have a defined acoustic resistance in order to dampen unwanted vibration modes and non-linear distortions of the membrane. Or it can have regions that generate acoustic resonance and thereby amplify or attenuate certain sound frequencies. Several sound paths with different path lengths and / or resonance frequencies can be realized in the same magnetic grid in order to influence different frequency ranges. Furthermore, (additional) regions of the magnetic grid can be made of a different, e.g., porous and thus acoustically absorbent material, preferably either as an insert or via 2K production, in order to influence the sound flow or, for example,to reduce unwanted reflections and modes. In this way, the various dimensions of sound (sound pressure, velocity, flow, radiation) can be shaped to ultimately achieve a specific sound quality and signature.

[0136] The magnet arrangement or the magnet grid can be made of an elastic material in areas adjacent to the higher-level assembly (e.g. housing) which provides acoustic sealing and decoupling of structure-borne sound and compensation of mechanical tolerances.

[0137] This aspect of the invention is based on the realization that elastic elements such as seals made of foam or silicone are often inserted between the sound transducer and the housing. These elements can be integrated into the magnetic grid as inserts or using a two-component manufacturing process, as previously mentioned, in order to eliminate the corresponding assembly step. The aim can be, on the one hand, sealing to prevent an acoustic short circuit between the front and back of the sound transducer, and, on the other hand, mechanical decoupling to reduce the transmission and audibility of structure-borne sound from the housing, cable or other parts to the sound transducer. Likewise, compensation for possible mechanical tolerances, i.e. mechanical dimensions and properties that vary during series production, can be achieved by more or less severe deformation of the elastic material.

[0138] The magnet arrangement or the magnetic grid, i.e. the arrangement and shape of webs and recesses, can essentially directly or inversely map the course of the conductor tracks on the membrane film and in particular in the area of ​​the connecting pieces, bends, etc., in order to focus the permanent magnetic field as best as possible and evenly on all sections of the conductor tracks.

[0139] This aspect of the invention is based on the realization that conventional implementations use magnetic bars that run parallel to the conductor tracks. The design freedom of the monolithic magnetic grid according to the invention can allow the turns or connections between the parallel conductor track segments to be precisely followed, either directly or inversely, and thus a constant magnetic field can be generated there as well, thus generating a homogeneous driving force across the entire membrane surface.

[0140] The conductor tracks and the corresponding magnetic poles of the grid can run in the direction of the longest dimension of the sound transducer (e.g., the long semi-axis of an ellipse) to minimize the number of parallel conductor track segments and the number of connecting pieces (turns). Thus, building on the previous aspect, it can also be advantageous if the parallel conductor track segments and the corresponding grid structure run in the direction of the longest dimension of the sound transducer to minimize the number and length of the turns or connecting pieces. This simplifies the manufacture of the grid and minimizes the number of conductor track pieces, which contribute little to driving the sound transducer in the edge region but increase the conductor length and electrical resistance, which can reduce the electrical current and thus the driving force.

[0141] Overall, the invention's aspects and features require a comparatively small number of individual parts. The assembly and quality assurance effort can be correspondingly very low, enabling cost-effective production at or below the cost of conventional dynamic or moving-coil transducers. Furthermore, the significantly improved sound quality of a planar dynamic transducer can be made available to a significantly expanded customer base.

[0142] Several embodiments and further advantages of the invention are described below in

[0143] The following figures are purely schematically illustrated and explained in more detail. Figure 1 shows a perspective, schematic, exploded view of a planar dynamic sound transducer according to a first embodiment, viewed obliquely from above;

[0144] Figure 2 is a perspective schematic exploded view of a planar dynamic sound transducer according to a second embodiment, viewed obliquely from above;

[0145] Figure 3 is a perspective schematic representation of a magnet arrangement of a planar dynamic sound transducer according to a third embodiment, viewed obliquely from above;

[0146] Figure 4 shows the representation of Figure 3 from below:

[0147] Figure 5 is a perspective cross-sectional view of a magnet arrangement of a planar dynamic sound transducer according to a fourth embodiment, viewed obliquely from above;

[0148] Figure 6 is a perspective cross-sectional view of a magnet arrangement of a planar dynamic sound transducer according to a fifth embodiment, viewed obliquely from below;

[0149] Figure 7 is a perspective cross-sectional view of a magnet arrangement of a planar dynamic sound transducer according to a sixth embodiment, viewed obliquely from above;

[0150] Figure 8 is a perspective cross-sectional view of a magnet arrangement of a planar dynamic sound transducer according to a seventh embodiment, viewed obliquely from above;

[0151] Figure 9 is a perspective cross-sectional view of a magnet arrangement of a planar dynamic sound transducer according to an eighth embodiment, viewed obliquely from above;

[0152] Figure 10 is a perspective cross-sectional view of a magnet arrangement of a planar dynamic sound transducer according to a ninth embodiment, viewed obliquely from above;

[0153] Figure 11 is a perspective cross-sectional view of a magnet arrangement of a planar dynamic sound transducer according to a tenth embodiment, viewed obliquely from above;

[0154] Figure 12 is a perspective cross-sectional view of a magnet arrangement of a planar dynamic sound transducer according to an eleventh embodiment, viewed obliquely from above;

[0155] Figure 13 is a perspective cross-sectional view of a magnet arrangement of a planar dynamic sound transducer according to a twelfth embodiment, viewed obliquely from above; and

[0156] Figure 14 is a view of Figure 13 from below. The above figures are viewed in Cartesian coordinates. There is a longitudinal direction X, which can also be referred to as depth X or length X. Perpendicular to the longitudinal direction X extends a transverse direction Y, which can also be referred to as width Y. Perpendicular to both the longitudinal direction X and the transverse direction Y extends a vertical direction Z, which can also be referred to as height Z and corresponds to the direction of gravity. The longitudinal direction X and the transverse direction Y together form the horizontal X, Y, which can also be referred to as the horizontal plane X, Y.

[0157] According to the first exemplary embodiment of Figure 1, a planar dynamic sound transducer 0 has, viewed from bottom to top in the vertical direction Z or perpendicular to the horizontal X, Y, a magnet arrangement 1, a membrane 2, a spacer element 3 and a protective grille 4, which, in the assembled state (not shown), are held together by fastening means 5 in the form of screws 5. The screws 5 can be removed non-destructively for the purpose of repair or disassembly. The planar dynamic sound transducer 0 or its corresponding elements, components or parts are essentially flat or planar in the horizontal X, Y and extend there in an oval with the longitudinal direction X as the preferred direction of extension.

[0158] The magnet arrangement 1, which can also be referred to as a magnetic grid 1, is formed in one piece, i.e. integrally or from one piece, as a magnetic body 1. The magnet arrangement 1 has an inner region 11, which in the first exemplary embodiment is designed as a depression 11 opposite an edge region 14. In this inner region 11, on the one hand, magnetic webs 12 with magnetic poles and, on the other hand, acoustic openings 13 are formed, which run parallel to the magnetic webs 12 in the longitudinal direction X and surround the magnetic webs 12 at one end and space them from one another in the transverse direction Y. The magnetic webs 12 are each connected to one another at the opposite end via the edge region 14 already mentioned.

[0159] The membrane 2, which is designed as a comparatively thin membrane foil 2, preferably less than 10 μm thick, is also formed integrally from a membrane body 20 made of a flexible material. A conductor track 21 made of electrically conductive material is applied to the membrane 2 and runs congruently with the acoustic openings 13 of the magnet arrangement 1. Accordingly, longitudinal sections 21a of the conductor track 21 run parallel to the acoustic openings 13 in the longitudinal direction X, and bends 21b of the conductor track 21 encircle the open ends of the magnetic webs 12 in the transverse direction Y.

[0160] The spacer element 3, which can also be referred to as the first ring 3, has a spacer element body 30, which is also formed in one piece. The spacer element 3 has an oval inner region 31 as a material-free through-opening in the vertical direction Z or perpendicular to the horizontal X, Y, so that the spacer element body 30 encloses the hollow inner region 31 in an oval shape.

[0161] The protective grille 4 closes off the planar dynamic sound transducer 0 at the top in the vertical direction Z or perpendicular to the horizontal X, Y, as shown in Figure 1. The protective grille 4 is also formed as a single piece as a protective grille body 40. In the inner area (not labeled), the protective grille body 40 has a plurality of acoustic openings 41, each of which is circular, evenly distributed, and surrounded by the protective grille body 40.

[0162] According to the invention, the edge region 14 has additional mechanical, acoustic, and electrical functions. This allows the functional scope of the planar dynamic sound transducer 0 to be expanded, its properties and quality to be improved, and / or its manufacture and, in particular, assembly to be simplified.

[0163] As a mechanical function of the planar dynamic sound transducer 0, the hold of the elements, components or parts is improved according to the invention in that the edge region 14 of the magnet arrangement 1 has a plurality of receptacles 15 in the form of bores 15 with internal threads, which are evenly distributed in the circumferential direction and can each accommodate the corresponding external threads of the screws 5. This allows for simple and secure assembly. The membrane 2 has corresponding through-openings 22 on the edge for fastening means 5 or for screws 5, the spacer element 3 has corresponding through-openings 32 on the edge for fastening means 5 or for screws 5, and the protective grille 4 has corresponding through-openings 42 on the edge for fastening means 5 or for screws 5, which are congruent with one another in the assembled state, so that the screws 5 can reach the receptacles 15 of the edge region 14 of the magnet arrangement 1.This can enable easy installation with a secure hold.

[0164] In order to align the receptacle 15 of the edge region 14 of the magnet arrangement 1 as simply, quickly, and reliably as possible with the through-openings 22 for fastening means 5 or for screws 5 of the membrane 2, with the through-openings 32 for fastening means 5 or for screws 5 of the spacer element 3, and with the through-openings 42 for fastening means 5 or for screws 5 of the protective grid 4, the edge region 15 of the magnet arrangement 1 further has a pair of guide pins 16 in the form of guide pins 16, which are diametrically opposed to one another. The membrane 2 has a corresponding pair of through-openings 23 for guide pins 16 of the magnet arrangement 1. Accordingly, the spacer element 3 also has a pair of through-openings 33 for guide pins 16 of the magnet arrangement 1. This applies accordingly to the protective grid 4, which in turn has a pair of through openings 43 for guide pins 16 of the magnet arrangement 1.

[0165] These through-openings 23, 33, 43 for guide pins 16 of the magnet assembly 1 are also arranged correspondingly to one another, so that the membrane 2, the spacer element 3, and finally the protective grille 4 can be positioned and held one after the other or together by means of the guide pins 16 of the magnet assembly 1, so that the screws 5 can then be screwed in as described above. This can further simplify assembly and, in particular, positioning and alignment with one another.

[0166] As an electrical function of the planar dynamic sound transducer 0, the invention enables contacting of the conductor track 21 of the membrane 2 at the edge region 14 of the magnet arrangement 1. For this purpose, the two conductor track ends 21c are designed as flat contact points 21c of the conductor track 21 and, pointing downwards in the vertical direction Z or perpendicular to the horizontal X, Y, are each connected by means of an electrically conductive adhesive to a corresponding contact element 17 or to a corresponding contact surface 17 for conductor tracks 21 of the membrane 2, so that an electrical connection is present between the membrane 2 and the magnet arrangement 1 at these two points.Through the magnetic body 10, the two contact surfaces 17 for conductor tracks 21 of the membrane 2 of the magnetic arrangement 1 are electrically conductively connected to outer contact elements 18 of the magnetic body 1 in the form of outer contact pins 18, which point radially outwards from the edge region 14 of the magnetic arrangement 1.

[0167] The two outer contact pins 18 of the edge region 14 of the magnet arrangement 1 are sufficiently solid so that electrical contact can be made from outside the planar dynamic sound transducer 0 by soldering using the two outer contact pins 18 of the edge region 14 of the magnet arrangement 1 in order to electrically feed the conductor track 21 of the membrane 2 and thus operate the planar dynamic sound transducer 0. Direct electrical contact of the conductor track ends 21c of the conductor track 21 of the membrane 2 from outside can thus be omitted, whereby the conductor track 21 of the membrane 2 or the membrane 2 can be designed to be comparatively thin or filigree and yet still be electrically contacted.

[0168] In any case, the magnetic body 10 of the magnetic assembly 1 can be formed in one piece, for example, using a two-component injection molding process (2K injection molding process), so that a plastic material such as a polyamide is present in the interior, into which permanent magnetic or hard magnetic particles such as neodymium-iron-boron are embedded. Using the 2K process, this inner region 11 of the magnetic body 1 is surrounded in one piece only by the same plastic material, so that the edge region 14 of the magnetic body 1 is formed free of hard magnetic particles. This allows the desired magnetic properties of the magnetic assembly 1 to be achieved in its interior region 11. At the same time, the manufacturing costs of the magnetic assembly 1 with regard to the material of the magnetic body 10 can be kept low, since the hard magnetic particles in the edge region 14 of the magnetic body 1 can be eliminated.

[0169] The planar dynamic sound transducer 1 of the second embodiment of Figure 2 essentially corresponds to the planar dynamic sound transducer 1 of the first embodiment of Figure 1.

[0170] However, the elements, components, or parts of the planar dynamic sound transducer 1 of the second embodiment of Figure 2 are held in place by the fact that four snap hooks 19 are integrally formed on the edge region 14 of the magnet assembly 1 of the magnet body 10. These snap hooks 19 can also be referred to as locking hooks 19 and extend upwards in the vertical direction Z or perpendicular to the horizontal X, Y. The hook elements (not designated) of the snap hooks 19 protrude radially inward, with the upper surfaces (not designated) of the hook elements being designed to extend obliquely inward. The four snap hooks 19 are positioned at the four corners of the oval surface of the magnet assembly 1.

[0171] The edge region 14 of the magnet arrangement 1 is flat or level with the inner region 11, so that the distance between the magnet arrangement 1 in the vertical direction Z or perpendicular to the horizontal X, Y upwards to the membrane 2 is achieved by an additional element, component or part in the form of a one-piece support element 6. The support element 6 can also be referred to as a receiving element 6, since it receives the membrane 2, or as a second ring 6. The support element 6 also has an oval inner region 61 as a material-free through-opening in the vertical direction Z or perpendicular to the horizontal X, Y, so that the support element body 60 encloses the hollow inner region 61 in an oval.

[0172] The elements, components, or parts of the planar dynamic sound transducer 1 of the second embodiment shown in Figure 2 are now assembled in such a way that the support element 6 is first pressed onto the magnet arrangement 1 from above, so that the snap hooks 19 are resiliently bent radially outwards to allow the support element body 60 to pass between them. This is done successively for the membrane 2, for the spacer element 3, and for the protective grille 4, which is then gripped from behind and held in place by the radially inwardly projecting hook elements in the vertical direction Z or perpendicular to the horizontal X, Y. This allows assembly without additional fastening means 5 or screws 5, which can simplify assembly and save material costs.

[0173] A secure hold in the vertical direction Z or perpendicular to the horizontal X, Y can be achieved if necessary by the

[0174] The support element 6 and / or the spacer element 3 can be made of an elastic material in order to exert a certain force from the inside or from below against the hook elements of the snap hooks 19 in the vertical direction Z or perpendicular to the horizontal X, Y. This also makes it possible to compensate for manufacturing tolerances of these elements, components, or parts in the vertical direction Z or perpendicular to the horizontal X, Y.

[0175] Simple and reliable positioning of the elements, components, or parts of the planar dynamic sound transducer 1 of the second embodiment shown in Figure 2 can be achieved by the oval shape of the contours of the elements, components, or parts, which corresponds to the arrangement of the snap hooks 19 and thus enables assembly as described above only in two mirror-symmetrical configurations. The design of the elements, components, or parts of the planar dynamic sound transducer 1 can be carried out accordingly.

[0176] Additionally, the upper ends of the snap hooks 19, which can be referred to as snap hook heads 19a or locking hook heads 19a, can be permanently magnetically designed at the top, so that other elements, components, or parts of the product in which the planar dynamic sound transducer 1 is used or installed can be magnetically releasably connected to the planar dynamic sound transducer 1 of the second embodiment of Figure 2. This can simplify the assembly of the product and / or create further possible uses.

[0177] In any case, the possibilities for electrically contacting the conductor track 21 of the membrane 2 described with regard to the first embodiment of the planar dynamic sound transducer 1 in Figure 1 can also be used in the second embodiment, in that the support element 6 now has a pair of contact elements 62 or contact surfaces 62 for conductor tracks 21 of the membrane film 2 as well as a pair of external contact elements 63 or external contact pins 63. As a result, the corresponding electrical function can also be implemented and used in the second embodiment as described above.

[0178] As an acoustic function, the magnet arrangement 1 or the magnetic grid 1 can be designed with regard to the specific configuration and arrangement of the acoustic openings 13 and the magnetic webs 12 or their magnetic poles in such a way that the sound field, sound pressure, sound velocity, or sound flow in the vicinity of the planar dynamic sound transducer 1 can be influenced, shaped in a frequency- or amplitude-dependent manner, or the vibration behavior of the membrane film 2 or other elements can be influenced in order to reduce or deliberately shape nonlinear distortions or frequency-dependent amplitude fluctuations in the generated sound signal. For this purpose, the grid structure of the magnetic webs 12 of the magnet arrangement 1 can be designed for full acoustic transparency with regard to the degree of opening and / or the shape of the acoustic openings 13.Alternatively, the acoustic openings 13 of the magnet assembly 1 can also have a defined acoustic resistance to dampen unwanted vibration modes and nonlinear distortions of the membrane 2. Alternatively, the acoustic openings 13 of the magnet assembly 1 can have regions that generate resonances and / or reflections, thereby amplifying or attenuating certain sound frequencies.

[0179] According to the illustrations in Figures 3 and 4, this can be implemented in concrete terms, for example, by providing horizontal cavities 12a of the magnetic webs 12 in the inner region 11 and horizontal cavities 14a of the edge region 14 in the longitudinal direction X or parallel to the longitudinal direction X as the greatest extent of the planar dynamic sound transducer 1 in the edge region 14. Likewise, the horizontal cavities 12a of the magnetic webs 12 can additionally extend in the transverse direction Y. In any case, sound can enter the cavities 12a, 14a from the acoustic openings 13 of the magnet arrangement through the horizontal cavities 12a of the magnetic webs 12 in the longitudinal direction X, through the horizontal cavities 12a of the magnetic webs 12 in the transverse direction Y and through the horizontal cavities 14a of the edge region 14 in the longitudinal direction X, or vice versa.For this purpose, these cavities 12a, 14a are provided with openings at selected positions through which sound flow can enter and exit.

[0180] In this way, as an acoustic function of the magnet arrangement 1, and in particular its edge region 14 and / or interior space 11, resonances and / or reflections can arise at certain sound frequencies, whose wavelengths are in a specific relationship to the respective cavity length or opening distance, which overlap with the regular sound radiation of the planar dynamic sound transducer 1. This overlap is constructive or destructive, depending on the phase position of the resonances and the spatial arrangement. Thus, at these frequencies, the sound emitted to the outside is amplified or attenuated.

[0181] Figure 5 shows a perspective cross-sectional view of a magnet arrangement 1 of a planar dynamic sound transducer 0 according to a fourth exemplary embodiment, viewed obliquely from above. Figure 5 represents a perspective view of a magnet arrangement 1 whose edge region 14 has been formed into a baffle 10a, which largely prevents an acoustic short circuit between the front and rear sides of the diaphragm in the relevant frequency range. Reference numeral 11 denotes the inner region with a grid structure formed from magnetic webs 12, which are integrally connected to non-magnetic webs 12b.

[0182] Figure 6 shows a perspective cross-sectional view of a magnet assembly 1 of a planar dynamic sound transducer 0 according to a fifth exemplary embodiment, viewed obliquely from below. Figure 6 represents a perspective view of a magnet assembly 1 whose edge region 14 has been formed into a front housing shell having a circumferential lateral wall 14b and bores 15 that can accommodate, for example, screws with which the front housing shell 7 can be connected to a rear housing shell 7 to create a closed housing.

[0183] Figure 7 shows a perspective cross-sectional view of a magnet arrangement 1 of a planar dynamic sound transducer 0 according to a sixth embodiment, viewed obliquely from above. Figure

[0184] 7 shows a perspective view of a magnet arrangement 1, the edge region 14 of which has been formed into a front housing shell having a circumferential lateral wall 14b and bores 15 which can accommodate, for example, screws with the aid of which the front wall or shell can be connected to a rear housing wall or shell (not shown) in order to obtain a closed housing. A further wall 14c, in conjunction with the rear housing wall (not shown), forms an acoustic channel of defined length which guides sound energy from the rear of the diaphragm through a first opening 14d to a sound outlet 14e, delaying it due to the sound propagation time and / or generating standing waves, whereby the radiated sound energy of the entire system can be influenced depending on the excitation frequency. 14f here denotes a raised support surface for a diaphragm.

[0185] Figure 8 shows a perspective cross-sectional view of a magnet arrangement 1 of a planar dynamic sound transducer 0 according to a seventh embodiment, viewed obliquely from above. Figure

[0186] Figure 8 shows a perspective view of a magnet assembly 1, the edge region 14 of which has been formed into a front housing shell having a circumferential lateral wall 14b and bores 15 that can accommodate, for example, screws, with the aid of which the front housing wall or shell (not shown) can be connected to a rear housing wall or shell (not shown) to obtain a closed housing. Two further walls 14c, in conjunction with the rear housing wall (not shown), form an acoustic channel of defined length, which encloses an acoustic mass for a resonance system between a first opening 14d and a sound outlet 14e.

[0187] Figure 9 shows a perspective cross-sectional view of a magnet arrangement 1 of a planar dynamic sound transducer 0 according to an eighth exemplary embodiment, viewed obliquely from above. Figure 9 represents a perspective view of a magnet arrangement 1 whose edge region 14 has been formed into a front housing shell having a circumferential lateral wall 14b and bores 15 that can accommodate, for example, screws with the aid of which the front housing wall or shell (not shown) can be connected to a rear housing wall or shell in order to obtain a closed housing. The edge region 14 contains an additional inner region 11a that is smaller than the first inner region 11, as well as an additional raised support surface 14h for an additional membrane.Due to its reduced dimensions, the additional sound transducer thus formed is better suited for reproducing higher sound frequencies than the sound transducer formed by the first inner region 11 and the membrane support 14f and the associated first membrane.

[0188] Figure 10 shows a perspective cross-sectional view of a magnet arrangement 1 of a planar dynamic sound transducer 0 according to a ninth embodiment, viewed obliquely from above. Figure

[0189] Figure 10 shows the magnet assembly 1 from Figure 9, which, in conjunction with a rear housing wall (not shown), forms a housing with an enclosed air volume. The latter is divided by the additional wall 14i into two separate air volumes, which are assigned to the first interior region 11 and the additional interior region 11a, respectively.

[0190] Figure 11 shows a perspective cross-sectional view of a magnet arrangement 1 of a planar dynamic sound transducer 0 according to a tenth exemplary embodiment, viewed obliquely from above. The interior region 11 is formed from several material components processed in the same manufacturing process, such as an injection molding process. In particular, the magnetic webs 12 in the Z direction are only as strong as necessary to provide a unidirectional, multipolar magnetic field. The magnetic webs 12 are mechanically supported or carried by additional webs 12b made of non-magnetic material, which are approximately congruent horizontally and adjacent vertically.

[0191] Figure 12 shows a perspective cross-sectional view of a magnet arrangement 1 of a planar dynamic sound transducer 0 according to an eleventh embodiment, viewed obliquely from above. 14 denotes the edge region, which simultaneously provides a raised support surface 14f for a diaphragm.

[0192] 11 designates the interior area with a grid structure, wherein outer openings or slots 13a have a smaller width than inner openings or slots 13b in order to concentrate the sound radiation onto the inner openings and to approximately convert the surface sound source into a line or point sound source.

[0193] Figure 13 shows a perspective cross-sectional view of a magnet arrangement 1 of a planar dynamic sound transducer 0 according to a twelfth exemplary embodiment, viewed obliquely from above. Figure 14 shows the view of Figure 13 viewed obliquely from below. Figure 13 (top side) and Figure 14 (bottom side) show the magnet arrangement 1 from Figure 9, with a different shape of the acoustic channel, which is formed by the lateral wall 14b and the further wall 14c. The edge region 14 continues outside the lateral wall 14b and thus merges seamlessly into a surface 14g, which is part of a larger structure and is shown here only for the sake of simplicity as a circular, flat disk.However, it can be shaped almost arbitrarily and, for example, form the back wall of a screen housing or a light, an outer surface of a piece of furniture or a ceiling suspension, or a paneling surface of a door, roof, dashboard, parcel shelf, footwell or seat of a vehicle. Further paneling, e.g. by attaching films, paneling materials or upholstery foam, is permissible, but should be designed to be largely acoustically transparent in the area of ​​the sound outlets. This integration into a larger, continuous structure requires that the sound outlet 14e lies essentially in the plane of the interior area 11 and thus emits sound outwards on the same side as the sound transducer. This applies accordingly when using a delay channel as shown in Figure 9.

[0194] LIST OF REFERENCE SYMBOLS (part of the description)

[0195] X longitudinal direction; depth; length

[0196] Y transverse direction; width

[0197] Z vertical direction; height

[0198] X, Y Horizontal; horizontal plane

[0199] 0 planar dynamic transducer

[0200] I Magnet arrangement; magnetic grid; magnetic system

[0201] 10 magnetic bodies

[0202] 10a baffle

[0203] II Interior; depression

[0204] 11a additional interior area

[0205] 12 magnetic bars

[0206] 12a (horizontal) cavities of the inner area 11 or the magnetic webs 12

[0207] 12b non-magnetic webs

[0208] 13 acoustic openings of the magnet arrangement 1

[0209] 13a Acoustic openings of smaller width of the magnet arrangement 1

[0210] 13b Acoustic openings of larger width of the magnet arrangement 1

[0211] 14 Marginal area

[0212] 14a (horizontal) cavities of the edge area 14

[0213] 14b lateral wall of the edge area 14

[0214] 14c further wall (acoustic channel) of the edge area 14

[0215] 14d first opening (acoustic channel) of the edge area 14

[0216] 14e Sound outlet (acoustic channel) of the edge area 14

[0217] 14f raised support surface for membrane of edge area 14

[0218] 14g Area (component of larger structure) of the edge area 14

[0219] 14h additional raised support surface for additional membrane of the edge area 14

[0220] 14i additional wall (separation of air volumes) of the edge area 14

[0221] 15 mounting holes for fasteners 5; holes with internal thread

[0222] 16 guide pins; guide pins

[0223] 17 Contact elements or contact surfaces for conductor tracks 21 of the membrane 2

[0224] 18 outer contact elements or outer contact pins

[0225] 19 snap hooks; locking hooks

[0226] 19a Snap hook head; locking hook head 2 Membrane; membrane foil

[0227] 20 membrane bodies

[0228] 21 Conductor track

[0229] 21a Longitudinal sections of the conductor track 21

[0230] 21b Sweeping the conductor track 21

[0231] 21c Conductor track ends; contact points of conductor track 21

[0232] 22 through holes for fasteners 5

[0233] 23 through holes for guide pins 16 of the magnet assembly 1

[0234] 3 spacer element; first ring

[0235] 30 spacer element bodies

[0236] 31 hollow interior

[0237] 32 through holes for fasteners 5

[0238] 33 through holes for guide pins 16 of the magnet assembly 1

[0239] 4 protective grilles

[0240] 40 protective grille bodies

[0241] 41 acoustic openings of the protective grille 4

[0242] 42 through holes for fasteners 5

[0243] 43 through holes for guide pins 16 of the magnet assembly 1

[0244] 5 fasteners; screws

[0245] 6 Support element; receiving element; second ring

[0246] 60 support element bodies

[0247] 61 hollow interior

[0248] 62 contact elements or contact surfaces for conductor tracks 21 of the membrane 2

[0249] 63 external contact elements or external contact pins

[0250] 7 rear housing shell

Claims

PATENT CLAIMS 1. Planar dynamic sound transducer (0) with at least one magnet arrangement (1) having a plurality of magnetic poles and with at least one acoustic opening (13) and with a diaphragm (2) having at least one conductor (21), wherein the magnet arrangement (1) has an inner region (11) which has the magnetic poles and an outer region (14) which surrounds the inner region (11) and connects its elements together, wherein the inner region (11) of the magnet arrangement (1) is offset perpendicular to the horizontal (X, Y) to the conductor (21) of the diaphragm (2) and is arranged in the horizontal (X, Y) at least overlapping, preferably congruent, to the conductor (21) of the diaphragm (2), characterized in that the outer region (14) of the magnet arrangement (1) further comprises at least one mechanical, acoustic and / or electrical function of the planar dynamic sound transducer (0).

2. Planar dynamic sound transducer (0) according to claim 1, wherein the inner region (11) of the magnet arrangement (1) and the edge region (14) of the magnet arrangement (1) are formed integrally from a magnet body (10) and at least the inner region (11) of the magnet arrangement (1), preferably exactly the inner region (11) of the magnet arrangement (1), comprises a hard magnetic material, preferably consisting of this.

3. Planar dynamic sound transducer (0) according to claim 1 or 2, wherein the outer region (14) of the magnet arrangement (1) is made of a different material than the inner region (11) of the magnet arrangement (1), preferably made of a material with a lower specific gravity and / or of a material with lower or no magnetization and / or of an elastic material.

4. Planar dynamic sound transducer (0) according to one of the preceding claims, wherein the inner region (11) of the magnet arrangement (1) is formed in a first process step from a first material and the outer region (14) of the magnet arrangement (1) is subsequently formed in a second process step from a second, different material. Planar dynamic sound transducer (0) according to any one of claims 1 to 3, wherein the outer region (14), preferably and sections of the inner region (11), of the magnet arrangement (1) is formed in a first process step from a first material and the, preferably remaining, inner region (11) of the magnet arrangement (1) is subsequently formed in a second process step from a second, different material. Planar dynamic sound transducer (0) according to any one of the preceding claims, wherein the outer region (14) comprises at least section by an elastic material, preferably formed section by section in a third process step from a third, different elastic material.Planar dynamic transducer (0) according to one of the preceding claims, wherein the edge region (14) of the magnet arrangement (1) is formed perpendicular to the horizontal (X, Y) higher than the inner region (11) of the magnet arrangement (1), wherein preferably the diaphragm (2) is in direct contact with the edge region (14) of the magnet arrangement (1). Planar dynamic transducer (0) according to claim 7, wherein the conductor track (21) of the diaphragm (2) is electrically connected at at least one conductor track end (21c), preferably at both conductor track ends (21c), to a contact element (17) of the edge region (14) of the magnet arrangement (1), and wherein the magnet arrangement (1), preferably the edge region (14) of the magnet arrangement (1), preferably each, has an outer contact element (18) which is configured to be electrically contacted from outside the magnet arrangement (1), preferably by soldering.Planar dynamic sound transducer (0) according to one of claims 1 to 7 with at least one support element (6) which is perpendicular to the horizontal (X, Y) between the. The edge region (14) of the magnet arrangement (1) and the membrane (2) is arranged and the The inner region (11) of the magnet arrangement (1) is spaced apart from the diaphragm (2) by means of a hollow inner region (61). Planar dynamic sound transducer (0) according to claim 9, wherein the conductor track (21) of the diaphragm (2) is electrically connected at at least one conductor track end (21c), preferably at both conductor track ends (21c), to a contact element (62) of the support element (6), and wherein the support element (6) preferably has an outer contact element (63) which is configured to be electrically contacted, preferably soldered, from outside the magnet arrangement (1). Planar dynamic sound transducer (0) according to any of the preceding claims, wherein the acoustic opening (13) of the magnet arrangement (1) follows the path of the conductor track (21) of the diaphragm (2) at least substantially, preferably completely.Planar dynamic transducer (0) according to any one of the preceding claims, wherein the acoustic opening (13) of the magnet arrangement (1) and the conductor track (21) of the diaphragm (2) extend substantially elongately and parallel to each other in the direction (X) of the greatest extent of the magnet arrangement (1). Planar dynamic transducer (0) according to any one of the preceding claims, wherein the edge region (14) of the magnet arrangement (1) has at least one guide pin (16), preferably a pair of guide pins (16), and the diaphragm (2), preferably a support element (6) and / or a spacer element (3) and / or a protective grille (4), has at least one through-opening (23), preferably a pair of through-openings (23), for the guide pin (16) of the magnet arrangement (1).Planar dynamic sound transducer (0) according to one of the preceding claims, wherein the edge region (14) of the magnet arrangement (1) has at least one receptacle (15), preferably a plurality of receptacles (15), for receiving a fastening means (5), preferably a screw (5), and wherein the diaphragm (2), preferably a support element (6) and / or a spacer element (3) and / or a protective grille (4), has at least one through-opening (22), preferably a plurality of through-openings (22), for the fastening means (5). Planar dynamic sound transducer (0) according to one of claims 1 to 13, wherein the edge region (14) of the magnet arrangement (1) has at least one snap hook (19), preferably a plurality of snap hooks (19), for gripping the diaphragm (2), preferably or a spacer element (3) or a protective grille (4), wherein preferably a snap hook head (19a) facing away from the magnet arrangement (1) is magnetically formed.Planar dynamic sound transducer (0) according to one of the preceding claims, wherein the edge region (14) has at least one, preferably horizontal, cavity (14a), preferably several, preferably horizontal, cavities (14a), which is open, preferably forming at least one acoustic opening (13), particularly preferably several acoustic openings (13), wherein the length of the cavity (14a) and / or the distance between two openings of the cavity (14a) is selected such that at least one sound frequency, whose wavelength is in a predetermined ratio to the length of the cavity (14a) and / or to the distance between two openings of the cavity (14a), experiences resonance and / or reflection.Planar dynamic sound transducer (0) according to one of the preceding claims, wherein the inner region (11), preferably at least one magnetic bridge (12), more preferably several magnetic bridges (12), and most preferably all magnetic bridges (12), of the inner region (11) comprises at least one, preferably horizontal, cavity (12a), more preferably several, more preferably horizontal, cavities (12a), which is open, preferably to at least one acoustic opening (13), more preferably to several acoustic openings (13), wherein the length of the cavity (12a) and / or the distance between two openings of the cavity (12a) is selected such that at least one sound frequency, the wavelength of which is in a predetermined ratio to the length of the cavity (12a) and / or to the distance between two openings of the cavity (12a), experiences resonance and / or reflection.Planar dynamic sound transducer (0) according to one of the preceding claims, wherein the inner area (11) is section by section acoustically more transparent, particularly for high sound frequencies, and otherwise acoustically less transparent, particularly for high sound frequencies.

19. Planar dynamic sound transducer (0) according to one of the preceding claims with a mirror-symmetrical pair of magnet arrangements (1) which surround the diaphragm (2) perpendicular to the horizontal (X, Y).

20. Planar dynamic sound transducer (0) according to one of the preceding claims, wherein the magnet arrangement (1) has at least one further inner region (11a) which has magnetic poles and is surrounded by the outer region (14).

21. Planar dynamic sound transducer (0) according to claim 20, wherein the edge region (14) of the magnet arrangement (1) has at least one additional wall (14f) which extends substantially outside the horizontal (X, Y) and acoustically separates the inner region (11) of the magnet arrangement (1) from the further inner region (11a).

22. Planar dynamic sound transducer (0) according to one of the preceding claims, wherein the magnet arrangement (1) has at least one further inner region (11) which is free of magnetic poles and is surrounded by the edge region (14).

23. Planar dynamic sound transducer (0) according to one of the preceding claims, wherein the edge region (14) of the magnet arrangement (1) is designed as a sound baffle (10c).

24. Planar dynamic sound transducer (0) according to one of the preceding claims, wherein the edge region (14) of the magnet arrangement (1) has at least one wall (14b) extending substantially outside the horizontal (X, Y), which encloses at least one inner region (11, 11a) at least sectionally.

25. Planar dynamic sound transducer (0) according to one of the preceding claims, wherein the magnet arrangement (1) together with a rear wall (7) forms an enclosure of the planar dynamic sound transducer (0), wherein the rear wall (7) is preferably, preferably by a film hinge, connected to the wall (14b) of the edge region (14) of the magnet arrangement (1), preferably formed in one piece.

26. Planar dynamic sound transducer (0) according to any one of the preceding claims, wherein the edge region (14) of the magnet arrangement (1) has at least one wall (14c) extending substantially outside the horizontal (X, Y), which forms at least one acoustic channel designed to communicate acoustically with the air volume above the interior region (11) and with the surrounding atmosphere.

27. Planar dynamic sound transducer (0) according to one of the preceding claims, wherein the edge region (14) of the magnet arrangement (1) has at least one surface element (14g) extending substantially in the horizontal (X, Y), preferably forming it in one piece.

28. Magnet arrangement (1) for use in a planar dynamic sound transducer (0) according to one of the preceding claims.

29. Listener, preferably headphones, with at least one planar dynamic sound transducer (0) according to one of claims 1 to 27.

30. Microphone with at least one planar dynamic sound transducer (0) according to one of claims 1 to 11.

31. Loudspeaker with at least one planar dynamic sound transducer (0) according to one of claims 1 to 11.

32. Loudspeaker-microphone combination with at least one planar dynamic sound transducer (0) according to claim 20 or 21, wherein at least the inner region (11) with an associated first diaphragm (2) is configured as a loudspeaker and at least the further inner region (11a) with an associated further diaphragm is configured as a microphone.

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