Abstract:
Children should be prevented from easily being able to remove the ear hook of a hearing aid. It is for this reason that a hearing aid that is to be worn behind an ear has a housing, which houses signal-processing components, and an ear hook, which is detachably attached to the housing. During the attachment process, the ear hook is moved toward the housing in an axial direction. The ear hook and the housing are embodied such that, in order to attach the ear hook to the housing, there is at least one movement of the ear hook in a second direction and a movement of the ear hook in a third direction, which differs from the second direction. Both the second and the third direction differ from the first direction. It follows that a complicated movement pattern is required when the ear hook is disassembled from the housing.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the priority, under 35 U.S.C. §119, of German application DE 10 2010 018 544.2, filed Apr. 28, 2010; the prior application is herewith incorporated by reference in its entirety. 
       BACKGROUND OF THE INVENTION 
     Field of the Invention 
       [0002]    The present invention relates to a hearing aid to be worn behind an ear. The hearing aid contains a housing, which houses signal-processing components, and an ear hook, which is embodied for detachable attachment to the housing. 
         [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 configuration 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 equipment 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]    Children and babies who are hard of hearing can be equipped with hearing aids. However, these instruments should be childproof. BTE hearing aids usually have an ear hook attached to the hearing-aid housing, the former serving to hold the hearing aid against the concha. 
         [0006]    However, since it should now be possible to remove the ear hook from the hearing aid or the hearing-aid housing for cleaning purposes, there is a problem in that the child or baby may remove the ear hook from the hearing aid and may possibly swallow it. 
         [0007]    At present, most ear hooks are affixed to the respective hearing aid using screw threads. However, in this case a child may also unscrew the ear hook from the hearing aid, which in turn leads to the safety issues outlined above. 
         [0008]    In order to solve this problem, a small amount of adhesive was in many cases previously applied to the ear hook such that a much higher force is necessary to remove the ear hook from the hearing aid. An alternative solution consists of affixing the ear hook to the housing with a fine thread such that, even after e.g. 20 rotations, the ear hook is still seated so securely and fixedly on the aid that there are no acoustic problems (feedback). 
       SUMMARY OF THE INVENTION 
       [0009]    It is accordingly an object of the invention to provide a hearing aid with ear-hook safety mechanism which overcomes the above-mentioned disadvantages of the prior art devices of this general type, in which an ear hook can be affixed in a simple and childproof fashion to the hearing-aid housing. 
         [0010]    According to the invention, the object is achieved by a hearing aid to be worn behind an ear, and containing a housing, which houses signal-processing components, and an ear hook, which is embodied for detachable attachment to the housing. The ear hook is moved toward the housing in a first direction during the attachment process, wherein the ear hook and the housing are embodied such that, in order to attach the ear hook to the housing, there is at least one movement of the ear hook in a second direction and a movement of the ear hook in a third direction, which differs from the second direction, wherein both the second and the third direction differ from the first direction. Here, both the second and the third direction can each have a directional component in the first direction. 
         [0011]    The different movement directions when attaching the ear hook advantageously ensure that it is not possible to remove the ear hook from the hearing aid by a simple sequence of movements. This significantly improves the child resistance. 
         [0012]    Preferably, a first adaptor is affixed to the housing and a second adaptor is affixed to the ear hook, and the two adaptors can be plugged into or onto one another in order to connect the ear hook to the housing. The adaptors can better take account of the mechanical necessities when connecting the ear hook to the housing, for example in respect of the choice of materials. 
         [0013]    One of the two adaptors may have at least one guide groove and the other adaptor may have at least one projecting element, and the at least one guide groove may be shaped such that the movements of the ear hook relative to the housing in the second and third direction emerge when the two adaptors are connected. The guide sleeve and the projecting element can easily force the desired movements. 
         [0014]    In a further exemplary embodiment, the two adaptors latch into one another in the state where they are completely plugged into or onto one another. This can securely bring the ear hook into a defined final position with respect to the housing. 
         [0015]    One of the two adaptors may at least partly consist of a metal. As a result, the respective adaptor can withstand relatively high forces. 
         [0016]    Moreover, a metal can reduce the abrasion with respect to most plastics. 
         [0017]    Furthermore, the second adaptor can have a sleeve-shaped configuration and can be completely inserted into a recess in the ear hook. This can provide an adaptor that is easy to build. 
         [0018]    Moreover, the first adaptor can have a tube port, through which sound is guided into the ear hook from the housing. The tube port then not only contains the function of guiding sound, but also the function of the adaptor. 
         [0019]    According to a further embodiment, the movement of the ear hook in the second direction is a clockwise screwing movement and the movement of the ear hook in the third direction is a counterclockwise screwing movement. The two different screwing movements reduce the possibility of chance disassembly by a child. 
         [0020]    In a further exemplary embodiment, in order to attach the ear hook to the housing, the ear hook may be moved in the first direction, followed by a movement in the second direction, then by another movement in the first direction and, following this, a movement in the third direction. Provision may also be made for other movement patterns with other sequences of the movement directions or additional movement directions. The movement pattern can increase the disassembly complexity as desired. 
         [0021]    In a preferred embodiment, the second direction has at least one directional component that is directed in the opposite direction to a directional component of the third direction. This means that a movement reversal is required during assembly and disassembly of the ear hook, which generally requires a deliberate action. 
         [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 aid with ear-hook safety mechanism, 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 hearing aid according to the prior art; 
           [0026]      FIG. 2  is a diagrammatic, perspective view of a first embodiment of a hearing aid with a disassembled hearing aid according to the invention; 
           [0027]      FIG. 3  is a diagrammatic, perspective view showing an interface between an ear hook and the hearing aid; 
           [0028]      FIG. 4  is a diagrammatic, perspective view of an ear-hook-side adaptor; 
           [0029]      FIG. 5  is a diagrammatic, perspective view of the adaptor from  FIG. 4 , inserted into an ear hook; 
           [0030]      FIG. 6  is a diagrammatic, perspective view of the ear hook and a housing-side adaptor as per a second embodiment according to the invention; 
           [0031]      FIG. 7  is a diagrammatic, perspective view of the ear hook from  FIG. 6  in a different perspective; 
           [0032]      FIG. 8  is a diagrammatic, perspective view of the housing-side adaptor from  FIG. 6  in an enlarged illustration; 
           [0033]      FIG. 9  is a diagrammatic, perspective view of the ear hook and the housing-side adaptor from  FIG. 6  in the assembled state; and 
           [0034]      FIG. 10  is a diagrammatic, enlarged side view of the housing-side adaptor from  FIG. 8 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0035]    The BTE hearing aid illustrated in  FIG. 2  in an exemplary fashion contains a housing  10 , in which conventional signal-processing components of the hearing aid are housed. A tube port or a sound-outlet port  11 , which protrudes out of the housing  10 , guides the output sound from the hearing aid out of the latter. The sound-outlet port  11  is tubular and is part of a housing-side adaptor that is similar to the one in  FIG. 8 . This first, housing-side adaptor generally has a very stable configuration since it serves to affix an ear hook  12 . Thus, it is produced from e.g. metal or ceramics, or at least has a metal core. 
         [0036]      FIG. 2  also shows that the ear hook  12  contains a sound channel  13  that runs from the end of the ear hook  12  facing the housing  10  to the end thereof facing away from the housing. At the end facing away from the housing  10 , the ear hook  12  has a circumferential thickened portion  14 , which serves to fix a sound tube (not illustrated). There is a cylindrical recess  16  on a side  15  of the ear hook facing the hearing-aid housing  10  and the sound channel  13  runs therein at the end face. The recess  16  serves to hold an ear-hook-side (second) adaptor  17 . The adaptor  17  has a sleeve-shaped configuration and entirely fits into the recess  16  of the ear hook  12 . 
         [0037]      FIG. 3  illustrates another perspective of the mechanical interface between the housing  10  and the ear hook  12  in an enlarged fashion. The housing-side adaptor  18  (first adaptor) contains a radially protruding lug  19  at its free end. It constitutes a projecting element, which guides the movement for affixing the ear hook  12  to the housing  10 . 
         [0038]    The ear-hook-side adaptor  17  has a guide  20  in which the lug  19  can be moved when the tube port  11  is pushed through the sleeve-shaped adaptor  17 . As mentioned previously, the ear-hook-side or the second adaptor  17  is in turn inserted into the recess  16  of the ear hook  12 . To this end, it can, for example, be snapped into the recess  16 , or attached therein in any other fashion (e.g. by adhesive bonding). So that it sits, secured against twisting, in the recess  16 , it has one or more projections  21 , which radially protrude from the outer shell of the sleeve-shaped adaptor. Accordingly, the recess  16  in the ear hook  12  also has corresponding notches  22 , and so there is anti-twist protection for the adaptor  17  in its inserted state. 
         [0039]      FIG. 4  shows the adaptor in an enlarged illustration. It has a hollow-cylindrical base body  23  with a guide  20 . The guide  20  has a first section, which runs in the axial direction (first direction). This first direction is labeled by an arrow  24 . This is adjoined by a second section of the guide  20 , which runs in the circumferential direction. In order to continue following the second section, starting from the first section, a movement in a clockwise second direction as per arrow  25  is necessary. A third section adjoins the second section of the guide  20 ; it once again runs in the axial direction (first direction). Should the lug  19  continue to be guided through the guide, it accordingly needs to carry out a movement as per arrow  26 . The guide now continues with a fourth section, which runs in the circumferential direction. This section accordingly prescribes a movement direction as per arrow  27 . Hence the lug  19  of the tube port  11  should be moved counterclockwise and hence also counter the movement direction  25  in the second section of the guide. A fifth section adjoins the fourth section at the end of the guide, and this fifth section once again runs in the axial direction. Hence, this results in an axial movement as per arrow  28  for the lug  19  of the tube port  11 . 
         [0040]    Thus, in order to assemble the hearing-aid housing  10  and the ear hook  12 , the latter must carry out movements as per arrows  24  to  28 . However, this supposes that an additional mechanism such as e.g. a magnet or a snap-fit element holds the ear hook  12  in its final position against the housing  10 . An alternative embodiment would consist of only movements as per arrows  24  to  27  being carried out and there being fixing in the circumferential direction at the end, for example by a latching element. 
         [0041]    Thus, mounting the ear hook  12  on the housing  10  requires a movement that needs opposing movements in two different sections. This is clarified in  FIG. 4  by the arrows  25  and  27 , which are directed in opposite directions despite both running in the circumferential direction. Hence the guide  20  leads to a very complex sequence of movements when assembling the ear hook. 
         [0042]    The ear hook  12  should be disassembled from the housing  10  in the reverse sequence. Thus, the movement denoted by the arrows  24  to  28  in  FIG. 4  should be carried out in reverse. The movement pattern is equally complex, and so the probability of a child inadvertently releasing the ear hook from the housing is reduced. 
         [0043]    As already mentioned in conjunction with  FIG. 3 , the second adaptor  17  has two projections, which protrude radially outward and serve as anti-twist protection.  FIG. 5  illustrates the state in which the second adaptor  17  is inserted into the recess  16  in the ear hook  12 . The projections  21  engage in corresponding notches or recesses  22  (see  FIG. 2  as well). 
         [0044]    A further exemplary embodiment will now be explained on the basis of  FIGS. 6 to 10 . Here the ear hook  12 , in which the sound channel  13  runs, is also plugged onto the first adaptor  18 . The hearing-aid housing is not illustrated in  FIG. 6 , but the first adaptor  18  is installed in the hearing-aid housing in the final assembled state (see  FIGS. 2 and 3 ). In the present example, it is merely the tip of the adaptor  18  that differs from the adaptor in  FIG. 3 . 
         [0045]      FIG. 7  shows the ear hook  12  from  FIG. 6  in that perspective from which it is possible to view the side  15  of the ear hook  12  that faces the hearing-aid housing. The ear hook  12  is made of a plastic. Like in the example of  FIG. 2 , it has a recess  16  on its side  15 . A metal sleeve  17  is inserted into the recess  16 . The sleeve  17  in this case also constitutes the second adaptor, into which the first adaptor  18  is plugged. The sleeve  17  has two hemispherical projections  30  as guide element. They project into the interior of the sleeve  17 . 
         [0046]    A corresponding housing-side adaptor  18  is illustrated in  FIG. 8 . It has a tube port  11 , which projects out of the housing, and a rear section  31  that runs in the hearing-aid housing. It substantially consists of a sound tube that ends at the tube port  11 . Attachment elements  32  with bores  33  are provided approximately in the middle of the adaptor in order to anchor the adaptor  18  fixedly in the housing. 
         [0047]    Depending on the requirements, the adaptor may be produced from different materials. On the one hand, it may be produced from plastics, metal or ceramics. However, it may moreover also contain a metal tube that is encased in plastic. 
         [0048]      FIG. 9  shows the assembly of ear hook  12  and adaptor  18 . Accordingly, the ear hook  12  is plugged onto the tube port  11  of the adaptor  18  in the axial direction thereof as per arrow  24 . However, in order to be plugged on, the ear hook  12  must follow a predetermined movement pattern compared to the adaptor  18 , as is likewise the case in the preceding exemplary embodiment. In the present case, the tube port  11  of the adaptor  18  as per  FIG. 10  contains a guide  40 , which is embodied as a groove in the shell surface of the tube port  11 . The guide  40  serves for guiding the hemispherical projection  30  of the second adaptor  17  in a predefined fashion. Accordingly, in this case it is first of all necessary, for plugging on purposes, for the ear hook to carry out a clockwise screwing movement. A first section  41  of the guide ensures this. As long as the hemispherical projection  30  is guided in this first section  41 , the ear hook  12  undergoes a screw-shaped movement, which contains a component in the axial direction and a counterclockwise component in the circumferential direction. 
         [0049]    A second section  42  adjoins the first section  41  of the guide  40 ; the second section  42  requires a counterclockwise screwing movement of the adaptor  12 . Thus, this second movement has a directional component in the axial direction and a counterclockwise directional component in the circumferential direction. 
         [0050]    The first section  41  of the guide  40  is connected to the second section by a curve. Moreover, there is an enlargement of the groove, or there is a depression  43  thereof, at the end of the second section, into which the hemispherical projection  30  of the first adaptor  17  can penetrate more deeply. This results in a latching position, which corresponds to the final assembled position of the ear hook  12  on the adaptor  18  or the housing  10 . 
         [0051]    Hence, a complex movement during the assembly of the ear hook  12  is also required in this case, which requires a movement with a certain directional component in one section, and a movement with an opposing directional component in a second movement section. 
         [0052]    The ear hook  12  is disassembled from the adaptor  18  against the arrow  34  in  FIG. 9 . To this end, the snap-fit connection must first of all be released in a first step with increased force and the hemispherical projection  30  must be rotated out of the depression  43 . The hemispherical projection  30  must subsequently be pushed out of the guide  40 , first of all along the second section  42  of the guide and subsequently along the first section  41  thereof. To this end, after the latching or snap-fit connection has been released, the ear hook  12  must, during its axial movement counter to the arrow  34 , firstly undergo a clockwise rotational movement and subsequently undergo a counterclockwise rotational movement. Overall, this results in the opposing movement pattern than during the assembly of the ear hook  12  onto the adaptor  18 . 
         [0053]    In order to ensure a secure guide corresponding to the desired movement pattern, a plurality of guides  40  can be arranged distributed over the circumference of the first adaptor  18 . A corresponding number of projections should then be provided on the second adaptor  17 . By way of example, two guides  40  are advantageously arranged at opposite locations on the tube port  11 . 
         [0054]    By way of example, the tube port  11  may be produced by insert molding using an injection molding process, wherein a metal tube, which forms the sound tube, is inserted into the mold while a shell with the guide  40  is injected around the tube. The inner metal tube  44  is indicated in  FIG. 8 . It ensures acoustic and mechanical stability. As a result of injection molding, complicated guides can be impressed into the adaptor with little effort. As a result, it is not that easy for children to remove the ear hook from the hearing aid, because knowledge relating to the system mechanism or the required movement pattern is required.