EP1432278A2 - Microphone module for a hearing aid - Google Patents

Abstract

The microphone module has a microphone carrier (1,1') to which several microphones (13,14,15; 13',14',15') are attached, provided by rigid plastics moulded part with 3-dimensional conductor paths for electrical connection of the microphones, e.g. for providing a directional microphone system.

Description

The invention relates to a microphone module for a hearing aid with a microphone holder to which several microphones are attached are, and a method for producing such Microphone module.

For cosmetic reasons there is a hearing aid Desire for extensive miniaturization of the devices. Furthermore, the devices should be as inexpensive as possible. Around To be able to achieve these goals will be very demanding the manufacturing and testing procedures. The production of individual modules before assembly of the hearing aid prefabricated and initially individually with regard to their functionality can be tested presents one possibility to reduce the manufacturing costs of a hearing aid.

Hearing aids with several microphones are known are arranged on a common carrier and thus a Form microphone module that as a structural unit in the housing of a Hearing aid installed or with the housing of a hearing aid can be connected. Such a hearing aid shows e.g. DE 196 35 229 A1.

Components are known from the electrical engineering industry, with injection molded plastic parts three-dimensional conductor tracks are provided. This Components are referred to as MID (Molded Interconnect Devices) and for example as a chip socket or plug connections used. The MID technology allows mechanical and combine electronic functions in one component. Thermoplastic mostly serves as the base material Plastics, but also thermosets or elastomers be used. The conductor tracks are usually applied directly to the component by metallization. Subsequently can other electronic components (resistors, Capacitors etc.) applied by gluing or soldering become.

DE 691 11 668 T2 describes a modular hearing aid with a Microphone, a receiver, an amplifier and a battery known, the microphone in a microphone module, the Receiver in a receiver module, the amplifier in one Amplifier module and the battery included in a battery module are. The individual modules can be removed by dovetail joints connected together. The individual modules are electrically connected by means of a flexible printed circuit board, which with contact points of the Module is soldered.

A hearing device is also known from US Pat. No. 6,456,720 in which several components electrically via a flexible printed circuit board are interconnected.

The object of the present invention is to manufacture to simplify a hearing aid with multiple microphones.

This task is solved by a microphone module for a Hearing aid with a microphone holder on which several microphones are attached, with the microphone carrier as a fixed Plastic molded part with three-dimensional conductive tracks is designed for electrical connection of the microphones.

a) Erzeugen eines Mikrofonträgers in Form eines festen Kunststoffformteils aus einem Kunststoffmaterial,

b) Aufbringen von dreidimensional geführten Leiterbahnen auf das Kunststoffmaterial,

c) Befestigen von Mikrofonen an dem Träger und Herstellen elektrischer Verbindungen zwischen Mikrofonkontakten und den Leiterbahnen.

Furthermore, the object is achieved by a method for producing a microphone module for a hearing aid device with the following steps:

a) producing a microphone carrier in the form of a solid molded plastic part from a plastic material,

b) applying three-dimensionally guided conductor tracks to the plastic material,

c) attaching microphones to the carrier and making electrical connections between microphone contacts and the conductor tracks.

In the manufacture of a microphone module according to the invention a microphone carrier is first created. This is preferred designed in such a way that everyone in one hearing aid existing microphones can be attached. To the acoustic Requirements for the microphones and the cramped Space in the housing of a hearing aid bill to wear, usually results for the microphone carrier inevitably an uneven shape. Now the microphone carrier should according to the invention not only the function of the attachment of microphones, but beyond advantageous additionally at least partially to the electrical Connection of the microphones with each other and with one electronic signal processing unit in the hearing aid serve. For almost any shape of the microphone carrier To enable this, it is preferably made of a thermoplastic, thermosetting or elastomeric plastic material built up. According to this plastic material the invention advantageously also directly for the conductor tracks electrical connection of the microphones applied. alternative can all or part of the conductor tracks from the Plastic material of the microphone carrier to be enclosed.

For metallizing and structuring the plastic carrier are different processes, especially from MID technology known, of which the most common are listed briefly should be:

In the hot stamping process, the plastic substrate is in one Metallized and structured step. With a stamp, on which the positive conductor pattern is applied a copper stamping foil with adhesion-promoting layer underneath Pressure and heat are pressed onto the plastic substrate. The substrate is affected by the heat on the surface melted. The conductor tracks are made from the copper foil cut out and bonded to the substrate.

Foil back injection is created by screen or pad printing a structured conductor pattern of a primer on a foil. During a conditioning process under temperature the primer establishes a chemical bond with the substrate surface and ensures good adhesive strength. In this process, the film is formed at the same time. Subsequently the film is placed in an injection molding machine and injected. After the injection, the Printed conductors galvanically reinforced and refined.

With the two-component injection molding process, the structure of the conductor pattern with a first injection molding made of metallizable Plastic made as a substrate for chemical Metallization serves. Depending on the plastic, the first injection molding treated the surface of the plastic become. The molding is placed in a mold again and encapsulated with non-metallizable plastic. The Free conductor tracks are then chemical metallized and refined.

In the mask process, the plastic carrier is metallized through chemical coating. Serves as a substrate a plastic injection molded part, in which first by pickling or etching the surface is prepared for germination. Then the metallization takes place. For structuring a photoresist is applied and by a three-dimensional Mask exposed to UV light. After developing the photoresist the exposed metal layer is galvanically reinforced and covered with an etching mask. After removing the The rest of the metal is etched away and then photoresists refines the surface.

In contrast to the mask process, direct laser structuring is used the etching resist is structured directly with the laser. At the points where the etch resist is caused by the laser the metal is etched away. In conclusion refines the surface.

In the LPKF laser direct structuring process, which after the The company LPKF is named, a plastic part is first injected. The structure picture is then transferred with a writing or imaging laser system. The subsequent metallization takes place in a chemically reductive Bath.

The formation of the microphone carrier in MID technology enables almost any shape of the microphone carrier as well as the creation of three-dimensionally guided conductor tracks on the microphone carrier or in the microphone carrier for the electrical connection of the microphones. This has several Benefits:

The microphone carrier makes the microphones simple and inexpensive way to a modular assembly - one Microphone module - summarized. For attaching the microphones can be soldered directly onto the microphone carrier become. This is also the electrical connection manufactured. Because the microphones through that on the microphone carrier applied conductor pattern already electrically with each other are connected, two lines are sufficient (positive pole, ground line) for the power supply of all microphones of the hearing aid, up to now two lines for each microphone required are. Furthermore, the microphones can after Assembly of the module before installation in a hearing aid in terms of their transfer behavior to one another be coordinated and tested.

Another advantage is that different Microphone modules, for example with two, three or more microphones can be populated in a simple manner generate a variety of different hearing aid variants leaves. Depending on the type of microphone module (e.g. equipped with two, three or four microphones) a hearing aid different functionalities of the resulting result Hearing aid and thus different hearing aid variants.

Furthermore, the invention offers the advantage that the microphone carrier in addition to the microphones with other electronic Components can be equipped. Is it the microphones to omnidirectional microphones, that's for training a directional microphone system an electrical connection of the Microphones required. The microphone signal at least one Microphones must be delayed and inverted and added to the microphone signal of another microphone can be added. Necessary for this Components, e.g. Delay elements and inverters, are advantageously placed directly on the microphone carrier, so that the microphone module itself is already a distinct one Polar pattern generated. The microphone carrier includes also the conductor tracks for the electrical connection of these components. In addition, most modern hearing aids are used digital signal processing. The invention enables also the installation of A / D converters on the microphone carrier, so that already digital signals from the microphone module to be delivered.

The electrical contacting of a microphone module according to the Invention can be both about strands, flex circuit boards or Connectors can be realized. It is also possible that the microphone module itself serves as a connector.

To generate a directional microphone system from several electrical interconnected omnidirectional microphones it is necessary that the microphones with regard to their amplitude and phase transfer behavior very precisely to one another are coordinated. Here, too, the invention offers advantages by electrical necessary for the microphone tuning Components (e.g. resistors and capacitors) directly on the microphone carrier are arranged. Can be advantageous the microphones already before installation in the hearing aid vote ("match"). Thus, a directional microphone system can be used as separate unit manufactured, compared and tested. Last but not least there are advantages for the Repair case of a hearing aid. Instead of defective microphones individually the entire microphone module is now replaced. This eliminates the need to compare an exchanged one Microphones with microphones remaining in the hearing aid.

The invention also makes it possible to use microphone modules so that they can be used in small hearing aids, e.g. hearing aids that fit behind the ear. The resulting reduction in the number also brings the connecting wires for the electrical connection of the microphones, e.g. from nine to five connecting wires for a microphone module with three microphones, through the associated softer Storage of the microphone module has an acoustic advantage.

Another embodiment of the invention provides a vibration-damped Storage of a microphone module according to the invention in a hearing aid. The vibration-damped bearing can both via the microphones as well as via the microphone carrier yourself. For example, the Microphones and also the sockets of the microphone inlets with elastic, vibration damping material, e.g. Rubber bags, overdrawn. A vibration-damping mounting of the individual This is microphones in the housing of a hearing aid not necessary anymore. Are also advantageous between the microphone carrier and receptacles for holding the microphone carrier Damping elements in the hearing aid housing elastic, vibration-damping material. So that's it entire microphone module vibration technology largely from that Decoupled housing of the hearing aid.

The microphone module according to the invention can be used in all usual Hearing aid designs are used, e.g. at in the ear portable hearing aids (ITE), wearable behind the ear Hearing aids (BTEs), pocket hearing aids etc.

Figur 1 einen Mikrofonträger in Seitenansicht,

Figur 2 einen Mikrofonträger von der Oberseite,

Figur 3 einen Mikrofonträger von der Unterseite,

Figur 4 einen mit drei Mikrofonen bestückten Mikrofonträger in Seitenansicht,

Figur 5 einen mit drei Mikrofonen bestückten Mikrofonträger von der Unterseite,

Figur 6 einen Teilbereich eines hinter dem Ohr tragbaren Hörhilfegerätes, in das ein Mikrofonmodul gemäß der Erfindung eingesetzt wird,

Figur 7 den Teilbereich sowie das Mikrofonmodul gemäß Figur 6, wobei die Mikrofone zur schwingungsdämpfenden Lagerung mit Taschen aus elastischem Material versehen sind, und

Figur 8 ein Mikrofonmodul, das ein elektrisches Bauteile zur Verschaltung der Mikrofone und Signalverarbeitung umfasst.

Further advantages and details of the invention result from the following description of exemplary embodiments. Show it:

FIG. 1 shows a microphone carrier in side view,

FIG. 2 shows a microphone carrier from the top,

FIG. 3 shows a microphone carrier from the bottom,

FIG. 4 is a side view of a microphone carrier equipped with three microphones,

FIG. 5 shows a microphone carrier equipped with three microphones from the underside,

FIG. 6 shows a partial area of a hearing aid device that can be worn behind the ear and into which a microphone module according to the invention is inserted,

FIG. 7 the partial area and the microphone module according to FIG. 6, the microphones being provided with pockets made of elastic material for vibration-damping mounting, and

FIG. 8 shows a microphone module which comprises an electrical component for connecting the microphones and signal processing.

Figure 1 shows a plastic injection molded part Microphone carrier 1 in side view. To form a microphone module can in the microphone carrier 1 three microphones the sections 1A, 1B and 1C of the microphone carrier 1 attached become. Two of the microphones are spatially separated by a bridge 1D the microphone carrier 1 separately.

In the manufacture of the microphone carrier according to the invention is a plastic injection molded part in a first process step produced in the form shown in Figure 1. For creating conductor tracks on the plastic injection molded part the process steps metallization and Structuring. Then be made on the so Microphone carrier 1 for fastening and electrical contacting soldered several microphones.

Figure 2 shows the microphone carrier 1 from the top. Out this view shows the ones applied directly to the microphone carrier 1 Conductor tracks 2-6 for electrical contacting of the microphones can be seen. It becomes clear that the two Conductor tracks 2 and 3 for powering the microphones each have contacts for contacting all three microphones. Furthermore, the microphone carrier 1 comprises one for each Microphone separate signal line 4-6. When assembling the microphone module this will be in the partial area shown in FIG 1A of the microphone carrier 1 arranged microphone with its Microphone contacts for mounting and electrical Connection soldered to the contact points 2C, 3C, and 6A. The Attachment and contacting of the other two microphones takes place on the underside of the microphone carrier 1. Therefore the conductor tracks 2-5 with bushings 2A, 2B, 3A, 3B, 4A and 5A provided on which the conductor tracks for the further course on the underside of the microphone carrier 1 through this are passed through.

Overall, the three microphones are connected electrically through the five conductor tracks 2-6. For connecting the microphone module with an amplifier (not shown) only five instead of nine connecting lines required so far. As a result, the microphone module helps to reduce manufacturing costs a hearing aid.

The underside of the microphone carrier 1 can be seen from FIG. The microphone carrier 1 in the exemplary embodiment also has conductor tracks on its underside, namely the conductor track 7 and 10 continuations of trace 2, the trace 8 and 11 continuations of trace 3, the trace 9 a continuation of the conductor track 4 and the conductor track 12 a continuation of the conductor track 5. The continuations of the Conductors are each - as described in Figure 2 - using bushings 2A, 2B, 3A, 3B, 4A and 5A for Continuation of the respective conductor track on the opposite Side of the microphone carrier 1 formed. The conductor track sections each end at the bottom of the microphone carrier 1 at a contact point 2D, 3D 4B (for a microphone) or 2E, 3E, 5B (for another microphone). The contact points for each microphone are separated by the bridge 1D Cut. Also the two microphones on the bottom of the Microphone carrier 1 are used for attachment and for electrical Connection with the contact points 2D, 3D 4B 2E, 3E and 5B soldered.

The microphone holder 1 with the three microphones attached to it 13, 14 and 15 are shown in FIG. 4. Each microphone has three Microphone contacts, of which only in Figure 4 the front microphone contact 13A, 14A and 15A can be seen is. The microphone 13 is on its microphone edge contacts Contact points 2C, 3C and 6A (see FIG. 2) on the top of the microphone carrier, the two microphones 14 and 15 with their microphone contacts at the contact points 2D, 3D, 4B or 2E, 3E and 4B on each side of the web 1D (cf. Figure 3). Five connecting cables 16-20 are also visible for the electrical connection of the microphone module with a Amplifier unit (not shown).

Figure 5 shows the microphone module with the microphone carrier 1 and the three microphones 13, 14 and 15 from the bottom. Out this view also shows three as sockets 13B, 14D and 15D trained sound inlets of the microphones 13-15 can be seen. Furthermore, from this view, the microphones 14 and 15 their microphone contacts 14A, 14B, 14C or 15A, 15B, 15C detect. These are at the contact points 2E, 3E, 5B or 2D, 3D, 4B soldered on opposite sides of the web 1D. FIG. 5 also shows the five connecting cables 16-20 for the electrical connection of the microphone module to an amplifier unit (not shown).

Figure 6 shows a detail of a wearable behind the ear Hearing aid 21, in which a microphone module according to the Invention is. The microphone module is located in FIG not yet fully installed in its final position Condition and therefore dominates the housing of the hearing aid 21 partially. Located on the top of the microphone holder 1 in the area of the connecting cables 16-20 on the conductor tracks one test port 23A-23E each for contacting one Test facility. This allows the correct function the microphone module before it is installed in the hearing aid check. Defective microphone modules can already do so sorted out early in the manufacturing process of the hearing aid become. Furthermore, FIG. 6 shows an uncut one shown area of the housing of the hearing aid 21 a sound passage opening 22. In this sound passage opening the socket protrudes when the microphone module is installed 13B of the microphone 13 (cannot be seen from FIG. 6; cf. Figure 5). The connecting pieces 14D, 15D of the others also project Microphones in corresponding further openings in the housing of the hearing aid 21 (not shown). This is the microphone module fixed in a simple manner in the hearing aid 21.

Figure 7 shows the section corresponding to Figure 6 of the hearing aid 21 with the microphone module according to the invention in plastic representation. However, they differ Figure 6 in the embodiment of Figure 7, the microphones as well as the sockets of pockets 24, 25 and 26 made of elastic, vibration-damping material that envelops even the microphone carrier partially enclose with. This is the fixation the microphone module in the hearing aid 21 and the vibration decoupling of the microphone module from the Housing of the hearing aid 21 improved. Furthermore can also be found at other connection points of the microphone carrier 1 with the housing of the hearing aid 21 damping elements located (not shown).

FIG. 8 shows a further development of the invention several arranged on a common microphone carrier 1 ' omnidirectional microphones 13 ', 14' and 15 'to form a Directional microphone system electrically interconnected. Advantageous are the electrical in this embodiment Interconnection of necessary electronic components, e.g. Delay elements and inverters, also directly on the Microphone carrier 1 'applied. The components are in the Assembly 27 'summarized in the embodiment arranged on the microphone carrier 1 'above the microphone 15' is. The assembly 27 'can be an integrated circuit and thus designed as an electronic component with its own housing his. However, several electrical ones can also be used Components can be placed on the microphone carrier 1 '. Also the conductor tracks for the electrical connection of the assembly 27 'are advantageously located directly on the microphone carrier. In this way, a directional microphone system can be easily created realize, in which also for the training of Directional microphone system required electronic components are included in the microphone module. Then they can Microphones 13 ', 14', 15 'of the microphone module have already been adjusted are inserted into a hearing aid before the microphone module becomes. The comparison with regard to the transmission behavior the microphones 13 ', 14', 15 'is particularly necessary if by electrical connection of the microphones a higher order directional microphone system is to be formed. Furthermore, the microphone carrier 1 'with other electrical Components are provided, adding functionality the microphone module e.g. is expanded to that too signal pre-amplification and A / D conversion of the microphone signals he follows. These components can also be of a single integrated circuit on the microphone carrier includes become. However, several electrical components can also be connected be attached to the microphone carrier 1 '. From the microphone module are already digital and therefore largely insensitive to interference Signals delivered at the signal outputs.

Claims (8)

Microphone module for a hearing aid (21) with a microphone carrier (1, 1 ') to which a plurality of microphones (13, 14, 15; 13', 14 ', 15') are attached, characterized in that the microphone carrier (1, 1 ') is designed as a solid plastic molded part with three-dimensionally guided conductor tracks (2-12) for the electrical connection of the microphones (13, 14, 15; 13', 14 ', 15'). Microphone module according to claim 1, characterized in that the microphones (13, 14, 15; 13 ', 14', 15 ') are electrically interconnectable to form a directional microphone system. Microphone module according to claim 1 or 2, characterized in that at least one electrical component (27 ') for connecting the microphones (13', 14 ', 15') to a directional microphone system is arranged on the microphone carrier (1 '). Microphone module according to one of Claims 1 to 3, characterized in that at least one electrical component (27 ') for amplitude and / or phase adjustment of the microphones (13', 14 ', 15') is arranged on the microphone carrier (1 '). Microphone module according to one of Claims 1 to 4, characterized in that at least one electrical component (27 ') for signal processing of the microphone signals generated by the microphones (13', 14 ', 15') is arranged on the microphone carrier (1 '). Microphone module according to one of claims 1 to 5, characterized in that the microphone carrier (1) comprises test ports for testing the microphones (13, 14, 15) attached to the microphone carrier (1). Microphone module according to one of claims 1 to 6, characterized by damping means (24, 25, 26) for vibration-damping mounting of the microphone module in the hearing aid (21). Method for producing a microphone module for a hearing aid (21) with the following steps: d) producing a microphone carrier (1; 1 ') in the form of a solid molded plastic part made of a plastic material, e) applying three-dimensionally guided conductor tracks (2-12) to the plastic material, f) attaching microphones (13, 14, 15; 13 ', 14', 15 ') to the microphone carrier (1; 1') and establishing electrical connections between microphone contacts (13A, 14A, 14B, 14C, 15A, 15B, 15C ) and the conductor tracks (2-12).

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