Abstract:
In a hearing aid provision can be made for a housing that is worn outside of an auditory canal of a user. Then, sound or electrical signals are conducted into the auditory canal from the housing. To this end, provision can be made for a conducting element such as a sound tube or a cable. The conducting element is then connected to the housing via a coupling element. This connection must be embodied such that the coupling element does not detach from the housing on its own accord. The user must be able to remove the coupling element and the conducting element from the housing in a simple fashion in order e.g. to be able to clean the former two parts. Accordingly, a coupling element and a housing can be interconnected in a detachable fashion, with this connection containing a dovetail joint for the hearing aid.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the priority, under 35 U.S.C. §119, of German application DE 10 2010 009 702.0, filed Mar. 1, 2010; the prior application is herewith incorporated by reference in its entirety. 
       BACKGROUND OF THE INVENTION 
     Field of the Invention 
       [0002]    The invention relates to a hearing device with a housing and a conducting element, by which sound or electrical signals can be conducted from the housing to another element of the hearing device, e.g. an earpiece. The conducting element is held against the housing by a coupling element. Here, the coupling element is connected to the housing in a reversibly detachable fashion, i.e. the coupling element can be detached from the housing without being destroyed and can also be reattached thereto. Here, the term hearing device is understood to mean a hearing aid in particular. However, the term moreover also encompasses other portable acoustic instruments, such as headsets, headphones or the like. 
         [0003]    Hearing aids are portable hearing devices used to support the hard of hearing. In order to make concessions for the numerous individual requirements, different types of hearing aids are provided, e.g. behind-the-ear (BTE) hearing aids, hearing aids with an external receiver (receiver in the canal [RIC]) and in-the-ear (ITE) hearing aids, for example concha hearing aids or canal hearing aids (ITE, CIC) as well. The hearing aids listed in an exemplary fashion are worn on the concha or in the auditory canal. Furthermore, bone conduction hearing aids, implantable or vibrotactile hearing aids are also commercially available. In this case, the damaged sense of hearing is stimulated either mechanically or electrically. 
         [0004]    In principle, the main components of hearing aids are an input transducer, an amplifier and an output transducer. In general, the input transducer is a sound receiver, e.g. a microphone, and/or an electromagnetic receiver, e.g. an induction coil. The output transducer is usually configured as an electroacoustic transducer, e.g. a miniaturized loudspeaker, or as an electromechanical transducer, e.g. a bone conduction receiver. The amplifier is usually integrated into a signal-processing unit. This basic configured is illustrated in  FIG. 1  using the example of a behind-the-ear hearing aid. One or more microphones  2  for recording the sound from the surroundings are installed in a hearing-aid housing  1  to be worn behind the ear. A signal-processing unit  3 , likewise integrated into the hearing-aid housing  1 , processes the microphone signals and amplifies them. The output signal of the signal-processing unit  3  is transferred to a loudspeaker or receiver  4 , which emits an acoustic signal. If necessary, the sound is transferred to the eardrum of the aid wearer using a sound tube, which is fixed in the auditory canal with an ear mold. A battery  5 , likewise integrated into the hearing-aid housing  1 , supplies the hearing aid and, in particular, the signal-processing unit  3  with energy. 
         [0005]    The sound tube of a hearing aid is a conducting element for conducting sound. It allows the targeted transmission of sound, produced in the receiver  4 , into the auditory canal. A connection between the sound tube and the hearing-aid housing  1  is often made possible by an ear hook. The latter can then also be used to hook the hearing-aid housing  1  behind an auricle of the aid wearer. The ear hook acoustically couples the sound tube to a sound-outlet opening of the housing  1 . Hence, it is a coupling element, by which sound produced by the receiver  4  can be guided into the sound tube. In the case of hearing aids that are not worn behind the ear, but rather e.g. in a concha of an auricle, a much smaller coupling element is used, instead of an ear hook, for connecting the sound tube to the hearing-aid housing. 
         [0006]    It must be possible to remove the coupling element of a hearing aid, and the sound tube connected thereto, from the hearing-aid housing in order to clean the sound tube or be able to replace the latter with a new sound tube. The aid wearer himself/herself should be able to undertake the removal. Hence, it must be possible to detach, and re-establish, the connection between the coupling element and the hearing-aid housing in the simplest possible fashion. On the other hand, the coupling element must not already detach from the housing if the aid wearer for example accidentally brushes along the sound tube with his/her hand and thereby pulls the coupling element. 
         [0007]    The coupling element is generally screwed onto a connection piece that protrudes from the housing. Sound, produced by a receiver in the interior of the housing, can also emerge from the housing through this connection piece. The sound-connection piece can have a male thread, onto which the coupling element can be screwed. However, a disadvantage of this connection is that after the coupling element has been screwed on and off a number of times, a thread in the interior of the coupling element is affected by wear and tear, and so the coupling element can no longer be connected to the housing in an acoustically sealed fashion. This can lead to undesired feedback of the sound produced by the receiver in a microphone of the hearing aid. Moreover, parts of the thread can detach from the coupling element and enter the sound-connection piece or the sound tube. This then negatively affects the transmission of the sound into the auditory canal. 
         [0008]    In a hearing aid with an external receiver (RIC), the sound is produced directly in the auditory canal of the aid wearer by an in-the-ear loudspeaker. In this hearing aid, provision is made for a cable, rather than a sound tube, between a housing of the hearing aid situated outside of the auditory canal and the loudspeaker. This cable serves as a conducting element for electrical signals that are transmitted from the housing outside of the auditory canal to the loudspeaker in the auditory canal. Here a cable is understood to mean an arrangement of one or more wires with associated insulation. 
         [0009]    A cable for an in-the-ear loudspeaker must also be connected to the housing situated outside of the auditory canal in a reversibly detachable fashion. As in the case of a sound tube, the aid wearer must find it easy to detach this connection as well. Nevertheless, it likewise must not detach on its own accord in the case of a slight pull on the cable. A corresponding coupling element for connecting the cable to the housing must not wear excessively quickly either because otherwise the coupling element would be seated too loosely on the housing and this would then result in sporadic interruptions of an electrical connection between contacts of the coupling element, on the one hand, and contacts of the housing, on the other hand. 
         [0010]    Another problem often associated with electrical contacts in hearing aids is that these contacts become dirty. Then, a desired electrical connection is no longer guaranteed when two contacts touch. Such contacts can also be situated in the interior of the housing of the hearing aid. In the case of such contacts situated on the inside, dirt can for example enter a shell of the housing, into which a switch of the hearing aid has been inserted, through a gap. 
       SUMMARY OF THE INVENTION 
       [0011]    It is accordingly an object of the invention to provide a hearing device with a conducting element, in particular a sound tube which overcomes the above-mentioned disadvantages of the prior art devices of this general type, which is an improve hearing device to the effect that it functions more reliably. 
         [0012]    The hearing device according to the invention contains a housing and a conducting element for conducting sound and/or electrical signals. The conducting element is held against the housing by a coupling element. The coupling element is connected to the housing in a reversibly detachable fashion. Here, the connection, by which the coupling element is connected to the housing, contains a dovetail joint. By way of example, such a dovetail joint can be provided by forming a projection, which is undercut on at least one side, on one of the two components, for example the housing. The other component can then be provided with a recess, by which the component can be pushed onto the projection. In the process, the undercut results in a form-fit in a direction at an angle to the direction of the push. 
         [0013]    Connecting the coupling element to the housing by a dovetail joint immediately results in a number of advantages. Compared to a connection by a thread, there is only little wear and tear on the components of a dovetail joint during the connection and detachment process. Hence, the conducting element can still be reliably connected to the housing after the coupling element has been detached from the housing, and reconnected thereto, a large number of times. Handling the hearing device according to the invention is also particularly simple. Thus, an aid wearer can connect the coupling element to the housing without much effort. Nor is there a risk in the case of a dovetail joint of parts of the coupling element becoming detached and for example blocking a sound tube. Further advantages emerging from the hearing device according to the invention are explained in conjunction with an exemplary embodiment. 
         [0014]    The hearing device according to the invention is advantageously developed by the coupling element for the connection to the housing being pushed on at an angle to a direction of extent, in which the conducting element extends away from the coupling element. Here it is particularly advantageous for the coupling element for the connection to the housing to be pushed on perpendicularly to this direction of extent. This results in the advantage of the coupling element not becoming detached from the housing if the aid wearer accidentally pulls on the conducting element. 
         [0015]    A further advantageous embodiment of the hearing device according to the invention arises from a housing-side component of the dovetail joint being configured in an integral fashion on a shell part of the housing. Then the shell part and the housing-side component of the dovetail joint can be produced in a single working step. This results in the advantage of being able to reduce the costs for producing a hearing device according to the invention. 
         [0016]    Should a sound transducer for producing sound be situated in the housing, an advantageous development arises from the housing and the coupling element each having a passage opening in the region of the dovetail joint. Sound produced in the interior of the housing can then emerge from the housing through this passage opening and enter the conducting element via the coupling element. This development is based on the discovery that the housing and the coupling element are held together particularly tightly in the region of the dovetail joint. Since the passage openings for transmitting the sound into the coupling element from the housing are provided in this region, this results in the advantage of allowing a particularly tight acoustic coupling between these two components. In other words, this particularly effectively prevents sound from undesirably emerging from the hearing device and causing feedback, as already described in conjunction with a sound-outlet connection piece. 
         [0017]    If the housing or the coupling element has a base, which is a component of the dovetail joint, an advantage furthermore arises if an end face of the base contains one of the passage openings. By way of example, such a base can form that projection in the dovetail joint with the already described undercut. In particular, a base should be understood to mean a raised structure with a cuboid basic shape. The end face is a face of the base where a surface normal points away from the housing. Providing one of the passage openings in the end face advantageously results in it being particularly simple to clean the hearing device in the region of the passage opening. 
         [0018]    A further advantage arises if one of the passage openings is surrounded by an O-ring. Such an arrangement can allow the hearing device to be particularly tight acoustically in the region of the dovetail joint. In doing so, this development is based on the discovery that the region in which the sound passes into the coupling element from the housing can also be sealed acoustically by an O-ring if part of the coupling element has to glide over the O-ring when the coupling element is pushed onto the housing. The O-ring is not damaged in the process. As soon as the coupling element has been completely pushed onto the housing such that the dovetail joint is established, the ring nevertheless seals as desired. O-rings as such are known from the prior art. However, these are usually used for sealing e.g. a line, made of two pipes that are stuck into one another, at a transition site between the pipes. 
         [0019]    Should, in the hearing device according to the invention, electrical signals be transmitted into the conducting element from the housing, an advantage arises if, in the region of the dovetail joint, the housing and the coupling element each have at least one electrical contact for transmitting an electrical signal. Then the contacts that need to touch in order to transmit the signal are pressed against one another particularly well. This advantageously ensures that there is an electrical connection even if there is e.g. dirt on the electrical contacts. This development of the hearing device according to the invention is also based on the discovery that the housing and the coupling element are held together particularly tightly in the region of the dovetail joint. 
         [0020]    Provision can be made for a conducting element to be configured both for conducting sound and for conducting electrical signals. Then, for example, a control signal for an active element in an auditory canal can also be conducted in addition to sound. An earpiece that can adjust its shape by an actuator is an example of such an active element. 
         [0021]    A further aspect of the invention relates to a conduction arrangement for the hearing device according to the invention. The conduction arrangement contains a conducting element for conducting sound and/or electrical signals, and a coupling element, by which the conducting element can be connected to a housing of the hearing device in a detachable fashion. It goes without saying that such a conduction arrangement can be produced independently of the remainder of the hearing device. 
         [0022]    Other features which are considered as characteristic for the invention are set forth in the appended claims. 
         [0023]    Although the invention is illustrated and described herein as embodied in a hearing device with a conducting element, in particular a sound tube, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims. 
         [0024]    The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         [0025]      FIG. 1  is a diagrammatic, illustration of a design of a behind-the-ear hearing aid, without sound tube or earpiece according to the prior art; 
           [0026]      FIG. 2  is a diagrammatic, side view of a hearing aid as per a first embodiment of the hearing device according to the invention; 
           [0027]      FIG. 3  is a perspective view of a housing-side component of a dovetail joint of the hearing aid illustrated in  FIG. 2 ; 
           [0028]      FIG. 4  is a perspective view of a coupling element and a sound tube connected thereto, which together form an embodiment of a conduction arrangement for the hearing aid illustrated in  FIG. 2 ; 
           [0029]      FIG. 5  is a cross-sectional view of a switch of a hearing aid, wherein gaps between the switch and a shell part of a housing are sealed by means of a film; 
           [0030]      FIG. 6  is a diagrammatic, side view of a second embodiment of the hearing aid according to the invention; and 
           [0031]      FIG. 7  is a diagrammatic, side view of a third embodiment of the hearing aid according to the invention 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0032]    Referring now to the figures of the drawing in detail and first, particularly, to  FIG. 2  thereof, there is shown a behind-the-ear hearing aid  10  with a housing  12 , an ear hook  14  and a sound tube  16 . The sound tube  16  has merely been illustrated in part. Part of the sound tube  16  that has not been illustrated extends beyond a break line  18  shown in  FIG. 2 . 
         [0033]    A configuration of the hearing aid  10  in an interior of the housing  12  is comparable to that of the hearing aid described in conjunction with  FIG. 1 . When a hearing-aid wearer wears the hearing aid  10 , the ear hook  14  and an attachment region  20  of the sound tube  16  rest against an auricle of the hearing-aid wearer such that the housing  12  is held behind the auricle as a result of this. 
         [0034]    The housing  12  is connected to the ear hook  14  in a reversibly detachable fashion by a dovetail joint  22 . The ear hook  14  is a coupling element for enabling the reversibly detachable connection between the sound tube  16  and the housing  12 . 
         [0035]    The flexibility of the sound tube  16  is constrained in the attachment region  20  because part of the attachment region sticks in a recess in the ear hook  14 . At an opening of the ear hook  14  formed by the recess, the sound tube  16  extends away from the ear hook  14  along a direction of extent  21 . 
         [0036]    An earpiece of the hearing aid  10 , by which the end of the sound tube  16  can be fixed in an auditory canal, is at one end of the sound tube  16 , not illustrated in  FIG. 2 . The sound tube is a conducting element for conducting sound to the earpiece. 
         [0037]      FIG. 3  once again illustrates the housing  12 , with the ear hook  14  (not illustrated) having been detached from the housing  12  in  FIG. 3 . The housing  12  has only been illustrated in part; the part that has not been illustrated extends beyond break lines  24 ,  25 . 
         [0038]    By detaching the ear hook  14  from the housing  12 , a planar surface  26  has been uncovered. A base  28  is formed on the housing  12  in the region of the surface  26 , which base constitutes a projection with respect to the surface  26 , i.e. the base  28  is a raised structure of the housing  12 . The base  28  can be integrally formed with a shell part of the housing  12 . 
         [0039]    The base  28  is part of the dovetail joint  22 . With respect to an end face  30  of the base  28 , side walls  32  of the base  28  are inclined such that there is an undercut  34  on the base  28 . The undercut  34  forms guides along which the ear hook  14  can be pushed onto the base  28  in order to form the dovetail joint  22 . Here, the ear hook  14  must be pushed onto the base  28  along a push direction  36 . The push direction  36  is perpendicular to a direction of extent  21 . 
         [0040]    Once the ear hook  14  has been pushed onto the base  28 , there is, in the region of the undercut  34 , a form-fit with respect to the direction of extent  21  between the base  28  and the ear hook  14 . Should the sound tube  16  then be pulled such that a force in the direction of the direction of extent  21  is exerted on the ear hook  14 , the ear hook  14  is held on the housing  12  against this force by the base  28 . Nevertheless, a user of the hearing aid can easily remove the ear hook  14  from the housing  12 . To this end, the user simply needs to push the ear hook  14  from the base  28  against the push direction  36 . 
         [0041]    The end face  30  has a sound-outlet opening  38 . Sound produced by a receiver in the interior of the housing  12  can emerge from the housing  12  through the sound-outlet opening. The sound-outlet opening  38  is surrounded by an O-ring  40 . The O-ring  40  is merely indicated by a dashed line in  FIG. 3 . When the ear hook  14  is connected to the housing  12 , the O-ring  40  presses against a wall of the ear hook  14  that is opposite to the end face  30 . As a result, the O-ring  40  prevents sound, emerging from the sound-outlet opening  38 , from escaping the hearing aid  10  from between the base  28  and the ear hook  14  in the region of the dovetail joint  22 . 
         [0042]      FIG. 4  illustrates the ear hook  14  on its own, i.e. without the housing  12 . The sound tube  16  is again only illustrated in part; a part that has not been illustrated extends beyond a break line  42 . The sound tube  16  is fixedly connected to the ear hook  14 . Together these two parts form a conduction arrangement for the hearing aid  10 . 
         [0043]    When the ear hook  14  is connected to the housing  12 , a contact surface  44  of the ear hook  14  butts against the surface  26  of the housing  12 . The contact surface  44  has a recess  46 . A shape of the ear hook  14  in the region of the recess  46  corresponds to a shape of the base  28 . The contours of edges of the ear hook  14 , which cannot be seen in the perspective view of  FIG. 4 , are indicated in  FIG. 4  by dashed lines. It can be seen that the ear hook  14  has an undercut  48  in the region of the recess  46 . The ear hook  14  can be pushed onto the housing  12  and onto the base  28  along the push direction  36  such that the base  28  glides into the recess  46  from the left-hand side in  FIG. 4 . The base  28  can be pushed into the recess  46  until it butts against a wall  50  of the ear hook  14 . The base  28  then completely fills the recess  46 . A sound-inlet opening  52  of the ear hook  14  then lies opposite the sound-outlet opening  38  such that sound can pass out of the housing  12  through the sound-outlet opening  38  and into the ear hook  14  through the sound-inlet opening  52 . From there the sound is then guided into the sound tube  16 . The sound-outlet opening  38  and the sound-inlet opening  52  are sound passage openings. 
         [0044]    The hearing aid  10  can be provided with a locking mechanism that then makes it possible to block a push movement that can push the ear hook  14  off the base  28 . By way of example, this then prevents an infant from independently being able to detach the ear hook  14  from the housing  12 . 
         [0045]    The dovetail joint allows a hearing-aid wearer to detach the ear hook from the housing with little effort. By allowing the base for the dovetail joint to be formed as a component of a shell part of the housing or of the ear hook, it is no longer necessary to provide e.g. a sound-connection piece made of steel as a separate component, as may be the case in a corresponding hearing aid from the prior art. Provision can also be made for the base to be configured as a component of a frame for holding a circuit arrangement of the hearing aid. This also results in the just-mentioned advantage. 
         [0046]    A hearing aid from the prior art can be redesigned with little effort in order to result in a hearing device according to the invention. Only a few working steps have to be modified to this end. After all, the example also shows how the dovetail joint and the O-ring ensure that the region between the housing and the ear hook is acoustically tight. 
         [0047]    The following text describes how dirt, such as dust or skin particles, and moisture, e.g. sweat or water, can be prevented from entering the interior of the housing in a hearing device, more particularly in a hearing aid. 
         [0048]    Dirt and moisture can corrode mechanical switches or surface mounted device (SMD) components of electrical circuits, or mechanically damage these in another fashion. Dirt and moisture often penetrate a gap situated between a switch of the hearing device and a housing part surrounding the switch. Hence, in general, it is attempted to configure these gaps to be as narrow as possible. However, the precision required for this during the production of the components makes a hearing device expensive. Provision can also be made for coating a surface of the hearing device such that sweat and water drip off the surface particularly well. However, this additional coating is also expensive. 
         [0049]      FIG. 5  shows a button  60  of a hearing device, by which button a user can switch an electrical switch  62 . By way of example, the button  60  can be produced from plastic, e.g. an acrylonitrile butadiene styrene copolymer (ABS), or rubber, e.g. silicone rubber. The switch  62  is part of an electrical circuit arrangement of the hearing device. A printed circuit board  64  of the circuit arrangement is also shown in  FIG. 5 . Further electrical and electronic components arranged on the printed circuit board  64  have not been illustrated. By way of example, the switch  62  can be a push switch, a rocker switch or a slide switch. 
         [0050]    The electrical switch  62  is situated in the interior of a housing of the hearing device. Of the housing,  FIG. 5  illustrates part of a housing shell  66 . The housing shell  66  can be produced from plastics, e.g. ABS. 
         [0051]    The button  60  is arranged in a passage opening of the housing shell  66 . The passage opening is larger than the button  60 , and so there are gaps  68  between the button  60  and the housing shell  66 . 
         [0052]    There is a film  70  on the outside of the hearing device. The film  70  adheres to the housing shell  66 . It can also adhere to the button  60 . The film  70  consists of an elastic material. By way of example, it can be produced from a polycarbonate (PC) or a polyethylene terephthalate (PET). The film  70  covers the gaps  68  toward the outside. As a result, neither dirt nor moisture can reach the interior of the hearing device, e.g. the printed circuit board  64 , through the gaps. 
         [0053]    The film  70  is elastic. In order to switch the switch  62 , a user moves the button  60  with respect to the housing shell  66 . This changes the width of the gaps  68 . Here, the film  70  adapts its shape to the position of the switch. 
         [0054]    The arrangement of the button  60 , the housing shell  66  and the film  70  can be produced as follows. The film  70  can initially be preformed. The film  70  is subsequently placed into a mold. The housing shell  66  is then molded onto the film  70  by injection molding. The button  60  is then molded onto the film  70  by a second mold, e.g. likewise by injection molding. 
         [0055]    In the hearing device illustrated in  FIG. 5 , the film  70  has a plurality of functions. First, it closes off the gaps  68  toward the outside, resulting in the previously described protection for the interior of the hearing device. The film  70  holds the button  60  in a certain position with respect to the housing shell  66 . This simplifies the assembly of the hearing device. 
         [0056]      FIG. 6  shows a behind-the-ear hearing aid  110  with a housing  112 , an ear hook  114  and a sound tube  116  with an attachment region  120 . In principle, the behind-the-ear hearing aid  110  corresponds to the instrument explained above with reference to  FIG. 2 ; to this extent, reference is made to the preceding explanations in the following text. 
         [0057]    The housing  112  is connected to the ear hook  114  in a reversibly detachable fashion by a dovetail joint  122 . Unlike the embodiment explained above, the dovetail joint  122  does not have straight edges but rounded edges  123 . 
         [0058]      FIG. 7  shows a behind-the-ear hearing aid  210  with a housing  212 , an ear hook  214  and a sound tube  216  with an attachment region  220 . In principle, the behind-the-ear hearing aid  210  corresponds to the instruments explained above with reference to  FIG. 2  and  FIG. 6 ; to this extent, reference is made to the preceding explanations in the following text. 
         [0059]    The housing  212  is connected to the ear hook  214  in a reversibly detachable fashion by a dovetail joint  222 . Unlike the embodiments explained above, the dovetail joint  222  has rounded edges  223  with an inverted curvature. 
         [0060]    The examples show how a detachable connection between an ear hook and a hearing-aid housing is made possible in a hearing device, wherein the connection can easily be detached and re-established by a user. This detachable connection also has particularly low wear and tear. Moreover, it is demonstrated how components in an interior of a housing in a hearing device can be protected from dirt and moisture.