Abstract:
A receiver assembly for a hearing aid device, the assembly comprising a case having an inner cavity, one or more mounts disposed within the inner cavity of the case, and a receiver disposed within the inner cavity of the case and connected to the mounts such that the receiver is suspended within the inner cavity of the case. The mounts dampen any vibration transmission from the receiver to the case and from the case to the receiver. Most significantly, acoustical noise from the receiver and any resulting distortion, feedback, and/or interference within the other components of the hearing aid device are substantially eliminated.

Description:
RELATED APPLICATIONS  
       [0001]    This application claims priority to Provisional Application Ser. No. 60/189,517, filed Mar. 15, 2000. 
     
    
     
       TECHNICAL FIELD  
         [0002]    The present invention relates to electro-mechanical acoustic transducers, and more particularly to miniaturized electroacoustic receiver transducers for use in miniaturized electronic devices, such as hearing aids.  
         BACKGROUND OF THE INVENTION  
         [0003]    Electroacoustic transducers are capable of converting electric energy to acoustic energy and vice versa. Electroacoustic receivers typically convert electric energy to acoustic energy through a motor assembly having a movable armature. Typically, the armature has one end that is free to move while the other end is fixed to a housing of the receiver. The assembly also includes a drive coil and one or more magnets, both capable of magnetically interacting with the armature. The armature is typically connected to a diaphragm near its movable end. When the drive coil is excited by an electrical signal, it magnetizes the armature. Interaction of the magnetized armature and the magnetic fields of the magnets causes the movable end of the armature to vibrate. Movement of the diaphragm connected to the armature produces sound for output to the human ear. Examples of such transducers are disclosed in U.S. Pat. Nos. 3,588,383, 4,272,654 and 5,193,116.  
           [0004]    Vibration of the armature and the receiver housing may cause acoustical noise in other components of the electronic device, such as a microphone. Such acoustical noise may cause distortion and feedback within the microphone, thereby reducing the quality of the device. Thus, there is a need to isolate other components of the electronic device from the vibrations created by the armature of the receiver.  
           [0005]    It is therefore an object of the present invention to provide a receiver assembly that is capable of isolating vibration created by the receiver from other components within the electronic device, such as a hearing aid.  
           [0006]    It is also an object of the present invention to provide a receiver assembly that is capable of isolating the receiver from vibration created externally from the receiver.  
           [0007]    These and other objects will become readily apparent after reviewing the specification and drawings.  
         SUMMARY OF THE INVENTION  
         [0008]    A receiver assembly for a hearing aid device, the assembly comprising a case having an inner cavity, one or more mounts disposed within the inner cavity of the case, and a receiver disposed within the inner cavity of the case and connected to the mounts such that the receiver is substantially suspended within the inner cavity of the case. The mounts are made of a material that is suitable to provide dampening of any vibration transmission from the receiver to the case. Most significantly, acoustical noise from the receiver and the resulting distortion, feedback, and/or interference within the other components of the hearing aid device is substantially eliminated. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    [0009]FIG. 1 is a perspective view of a first embodiment of the present invention.  
         [0010]    [0010]FIG. 2 is a top plan view of the embodiment shown in FIG. 1.  
         [0011]    [0011]FIG. 3 is a cross-sectional side elevational view taken along section line A-A shown in FIG. 2.  
         [0012]    [0012]FIG. 4 is a side elevational view of the embodiment shown in FIG. 1.  
         [0013]    [0013]FIG. 5 is a first perspective cutaway view of the embodiment shown in FIG. 1 wherein one side of the case is cut away.  
         [0014]    [0014]FIG. 6 is a second perspective cutaway view of the embodiment shown in FIG. 1 wherein one side of the case is cut away.  
         [0015]    [0015]FIG. 7 is a perspective view of a second embodiment of the present invention.  
         [0016]    [0016]FIG. 8 is a top plan view of the embodiment shown in FIG. 7.  
         [0017]    [0017]FIG. 9 is a cross-sectional side elevational view taken along section line A-A shown in FIG. 8.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0018]    While the present invention will be described fully hereinafter with reference to the accompanying drawings, in which particular embodiments are shown, it is to be understood at the outset that persons skilled in the art may modify the invention herein described while still achieving the desired result of this invention. Accordingly, the description which follows is to be understood as a broad informative disclosure directed to persons skilled in the appropriate arts and not as limitations of the present invention.  
         [0019]    A receiver assembly  10  of the present invention is shown in FIGS.  1 - 6 . The receiver assembly  10  isolates a receiver  11  from vibration transmission, as shown in FIG. 3. The terms vibration and acoustical noise may be used interchangeably within this specification and are intended to have the same meaning. The receiver assembly  10  includes a first case half  12  and a second case half  14  that form an outer case  16 , as shown in FIG. 1. The outer case  16  defines an inner cavity  18 . The outer case  16  includes a first end surface  20  and a second end surface  22 . The case  16  has a first aperture  24  within the first end surface  20  and a second aperture  26  within the second end surface  22 . The first aperture  24  defines a first aperture edge surface  28  of the case  16 . The second aperture  26  defines a second aperture edge surface  30  of the case  16 . A hollow cylindrical sleeve  32  is disposed within the first aperture  24  and defines an outlet port  34  having a port opening  36 . The cylindrical sleeve  32  includes an outwardly radially protruding annular shoulder  38  defining an outer annular surface  40 . The outer annular surface  40  has an annular groove  42  therein. The first aperture edge surface  28  is mated with the annular groove  42  to secure the cylindrical sleeve  32  to the case  16 . The cylindrical sleeve  32  may additionally be attached to the case  16  by other means, such as adhesive or through insert molding with the case  16 . The sleeve  32  may also be integrally formed with the case  16 .  
         [0020]    A mounting pin  44  is disposed within the second aperture  26  of the case  16 , as shown in FIG. 3. The mounting pin  44  includes a central pin portion  46 , a first disk  48  disposed on one end of the central pin portion  46 , and a second disk  50  disposed on the other end of the central pin portion  46 . The first and second disks  48  and  50  are larger than the second aperture  26  of the case  16 . The central pin portion  46  of the mounting pin  44  mates with the edge surface  30  of the case  16 . The disks  48  and  50  prevent the mounting pin  44  from sliding out through the second aperture  26 . In a preferred embodiment, the pin is made of metal. However, other materials, such as plastic or other polymeric resins may also be used.  
         [0021]    A first mount  52  of the receiver assembly  10  includes a mounting base  54  having a mounting surface  56  and a cylindrical extension  58  having a bore  60  extending therethrough, as shown in FIG. 3. The first mount  52  is preferably made of an elastomeric material, such as silicon rubber. However, any material that can be utilized as a vibration dampening spring may also be used. The durometer of the mount  52  varies according to the material used and the dimensions of the mount  52 . The first mount  52  is positioned such that the cylindrical extension  58  is disposed within the cylindrical sleeve  28  and the mounting base  54  is disposed within the inner cavity  18  of the case  16 . As shown in FIG. 3, the cylindrical extension  58  has an outer cylindrical surface  62  and includes an annular shoulder  64  that extends radially outwardly from the outer cylindrical surface  62 . The shoulder  64  defines a shoulder surface  66  that mates with an annular surface  68  within the cylindrical sleeve  28 . The shoulder  64  prevents the cylindrical extension  58  of the first mount  52  from moving outwardly past the port opening  36 . The connection of the first mount  52  to the case  16  is best shown in FIG. 5. Alternatively, the first mount  52  may also be connected to the case  16  through insert molding or an adhesive. The first mount  52  may also be integrally formed with the case  16 .  
         [0022]    A second mount  70  of the receiver assembly  10  includes a mounting base  72  having a mounting surface  74  and a shallow cylindrical bore  76 . The second mount  70  is disposed within the inner cavity  18  of the case  16  and secured to the case  16  by the mounting pin  44 . Alternatively, the second mount may also be secured to the case by insert molding, adhesive, or integrally formed with the case  16 . The second mount  70  is positioned such that the second disk  50  of the mounting pin  44  is disposed within the cylindrical bore  76  of the second mount  44 . The second mount  70  is preferably made of an elastomeric material, such as silicon rubber. However, any material that can be utilized as a vibration dampening spring may also be used. As with the first mount  52 , the durometer of the second mount  70  varies according to the material used and the dimensions of the second mount  70 . The connection of the second mount  70  to the case  16  is best shown in FIG. 6.  
         [0023]    The receiver  11  is disposed between the first and second mounts  52  and  70  and mounted to the mounting surfaces  56  and  74  of the mounts  52  and  70 , as shown in FIG. 3. The receiver  11  may be mounted to the mounting surfaces  56  and  74  by any mechanical means, such as a fastener, adhesive, friction fit, compression fit, or the like. The mounts  52  and  70  may also be insert molded with the receiver housing. The receiver  11  is thereby suspended within the inner cavity  18  of the case  16 . The mounts  52  and  70  dampen vibrations emanating from the receiver  11  and minimize vibrations from transmitting to the case  16 . The mounts also isolate the receiver  11  from any vibrations occurring outside the case  16 . As shown in FIG. 4, a terminal aperture  78  is provided within the second end surface  22  of the case  16  so that the terminals (not shown) of the receiver  11  can pass therethrough.  
         [0024]    A second embodiment of the present invention is shown in FIGS.  7 - 9  as a receiver assembly  100 . In this embodiment, an integrally formed mount  102  is disposed within a first aperture  104  of a case  106 . The mount  102  includes a mount tab  108 , a central neck portion  110 , and a mounting base  112  all integrally formed in a single piece. Thus, the mount  102  is a single piece as opposed to the two-piece configuration of the first embodiment.  
         [0025]    The receiver assembly  100  also includes a cylindrical sleeve  114  that is a modified version of the cylindrical sleeve  28  of the first embodiment. The cylindrical sleeve  114  does not include an annular surface within the cylindrical sleeve to prevent the cylindrical extension of the mount from sliding through the port opening, as in the first embodiment. In the second embodiment, an annular shoulder  116  is disposed on a cylindrical extension  118  of a mount  120  and is frictionally fit within the cylindrical sleeve  114 . This second embodiment also effectively isolates the receiver  11  from transmitting vibrations. The mounts  102  and  120  act together to dampen vibration transmission from the receiver  11 . The mounts also may act to dampen vibration transmission to the receiver through the case  106 .  
         [0026]    The scope of the present invention also includes a method of assembling a receiver assembly. The method comprises the steps of:  
         [0027]    (1) mounting a first mount having a hollow cylindrical extension to a receiver;  
         [0028]    (2) mounting a second mount having a bore to the receiver;  
         [0029]    (3) inserting the cylindrical extension of the first mount into a cylindrical sleeve;  
         [0030]    (4) inserting one end of a mounting pin into the bore in the second mount;  
         [0031]    (5) inserting the receiver into a first case portion having two apertures such that the other end of the mounting pin is disposed within one aperture of the first case portion and the cylindrical sleeve is disposed within the other aperture of the first case portion;  
         [0032]    (6) placing a second case portion over the receiver inserted into the first case portion; and  
         [0033]    (7) joining the first and second case portions together.  
         [0034]    It is apparent that one or more steps of assembly may be eliminated by integrally forming various components with other components of the device as described herein. Furthermore, the method used to join the case portions will depend on material selections. If plastic or metal is used for the case portions, they may be joined by welding, adhesive, or other mechanical means.  
         [0035]    While the specific embodiments have been illustrated and described, numerous modifications may come to mind without significantly departing from the spirit of the invention, and the scope of protection is only limited by the scope of the accompanying claims.