Patent Abstract:
A portion of a hearing instrument housing or shell comprises one or more chambers having planar, conical, or convex walls. During assembly, this shape helps guide the receiver tube towards tip of the shell and the receiver tube hole. Additionally, it will reinforce the walls of the shell, decreasing the tendency of the shell to vibrate when the receiver is generating sound.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is related to the following U.S. patent applications, incorporated herein by reference:  
         [0002]     Ser. No. 09/887,939 filed Jun. 22, 2001;  
         [0003]     Ser. No. 10/218,013 filed Aug. 13, 2002;  
         [0004]     Ser. No. 10/610,449 filed Jun. 30, 2003; and  
         [0005]     Ser. No. 10/945,704 filed Sep. 21, 2004. 
     
    
     BACKGROUND AND SUMMARY OF THE INVENTION  
       [0006]     Hearing instruments, i.e., devices that assist the hearing impaired, designed for complete or partial insertion into the user&#39;s ear canal, have a shell or housing that holds various components. One such component is the receiver, the element that generates the sound heard by the instrument&#39;s user. The sound is carried from the receiver by a receiver tube affixed to a port on the receiver to an opening (the receiver tube hole) in the tip of the shell, the portion of the hearing instrument positioned in the ear canal towards the eardrum.  
         [0007]     During assembly, the receiver and its receiver tube are inserted into the shell, receiver tube first, and the tube is passed through the receiver tube hole. Once the receiver is in place inside the shell, anchored by a support, any excess portion of the receiver tube protruding from the shell is removed.  
         [0008]     During assembly, the receiver tube is inserted into the shell and aimed towards the receiver tube hole. Occasionally, the end of the tube misses the receiver tube hole and catches on the inside of the shell. In that instance, the receiver tube must be pulled out and reinserted in an attempt to pass the tube through the receiver hole.  
         [0009]     An Improved Configuration for the Inside of the Shell  
         [0010]     The problem mentioned above may be minimized by providing an inwardly-sloping contour inside the shell of the hearing instrument. In particular, the interior of at least a portion of the shell comprises a chamber having planar or conical surfaces or inwardly curving or convex surfaces that guide the receiver tube towards the tip of the shell and the receiver tube hole.  
         [0011]     Depending on the size and length of the hearing instrument, the shell may contain more than one such chamber. For example, where there are two chambers, the receiver tube is inserted into and through the first chamber and the tube then passes through an optional interconnecting passage and into and through the second chamber. A stopper having dimensions greater than the interconnecting passage may be provided on the receiver tube. When the stopper meets the end of the first chamber, the tube will not travel further into the shell, fixing the location of the receiver in the shell. A stopper may also be provided for a shell having a single chamber.  
         [0012]     The design discussed here will improve the assembly process. An additional benefit achieved by the configurations discussed here is that walls of the shell are reinforced, reducing any tendency of the walls to vibrate. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]      FIGS. 1 and 2  are partial cross-sectional views of hearing instrument shells comprising a single chamber;  
         [0014]      FIGS. 3, 4 ,  5 , and  6  are partial cross-sectional views of hearing instrument shells comprising two chambers;  
         [0015]      FIG. 7  is a partial axial cross-sectional view of a chamber and a conforming stopper for a receiver tube; and  
         [0016]      FIGS. 8 and 9  are partial cross-sectional views of a hearing instrument shell comprising a chamber having multiple angular profiles or contours. 
     
    
     DESCRIPTION OF THE INVENTION  
       [0017]      FIG. 1  is a partial cross-sectional view of a hearing instrument shell or housing  10 , comprising a tip  12  to be inserted into the ear canal of the person wearing the hearing instrument. The other end of the shell  10 , on the right side of  FIG. 1 , shown incomplete in this as well as the other figures, is where the faceplate  20  (shown schematically here) would be attached. The faceplate  20  is the portion of the hearing instrument that faces generally outwardly from the ear proper, and at least a portion of the faceplate  20  is typically visible in the outer ear. In addition to an opening to admit sound, the faceplate  20  may also contain a battery door and a volume control. The faceplate may be fabricated as an integral component of the housing or shell  10  or it may be a separate part attached to the housing or shell  10  during assembly.  
         [0018]     A receiver assembly  100  is positioned in the interior  200  of the shell  10  and may be mounted there using anchors  16  such as those described in U.S. application Ser. No. 10/945,704 and schematically depicted here in  FIG. 1 . A flexible receiver tube  300 , having a degree of resilience and compliance, conveys the sound generated by the receiver  100  to the outside of the instrument housing  10 . The receiver tube  300  is attached to the receiver assembly  100  and the end  302  of the receiver tube  300  passes through a receiver tube hole  14  in the tip  12  of the shell  10 .  
         [0019]     At least a portion of the shell interior  200  is a forward chamber  210  located in the tip  12  of the hearing instrument shell  10 . As illustrated in  FIG. 1 , the forward chamber  210  is oriented such that the narrow end  212  of the chamber  210  is near the tip  12 ; the wide end  214  of the chamber  210  is closer to the faceplate  20 . Depending on design and space considerations, the receiver  100  may reside at least partially within the forward chamber  210 .  
         [0020]     In the configuration illustrated in  FIG. 1 , the walls or surfaces  216  of the forward chamber  210  are depicted as straight lines. In such a case, those surfaces  216  may be conical or planar. The geometry of the chamber  210  would then be either conical or polyhedral, respectively, and may be truncated at the receiver tube hole  14 . Also, a chamber  210  comprising a polyhedral contour may have sides (i.e., portions of the walls  216 ) of equal or unequal dimensions. Alternatively, the walls or surfaces  216  may curve inwardly, defining convex surfaces such as a hyperboloid (technically, one-half of a hyperboloid), as illustrated in  FIG. 2 .  
         [0021]     The entire chamber  210  or a portion of the chamber  210  may exhibit the desired planar, conical, or convex shape. In  FIG. 1 , however, only the portion of the chamber  210  closest to the tip  12  has this shape (i.e., planar or conical). The rear portion  202  of the shell interior  200 , where the bulk of the receiver  100  is positioned, follows the outer contour of the shell  10  to a greater or lesser degree. Similarly, only the portion of the chamber  210  illustrated in  FIG. 2  adjacent to the tip  12  has a convex contour.  
         [0022]     If desired, a stopper  310  may be provided for the receiver tube  300 , as shown in  FIG. 1 . The stopper  310  may be an integral part of the receiver tube  300  or an added piece that sits on the outside of the tube  300 . As appropriate, the shape of the stopper  310  can be fashioned to conform to the shape of the walls  216  of the forward chamber  210  or it can assume the shape of a truncated cone (also known as a conical frustrum), a torus, a sphere, or some other suitable configuration.  
         [0023]     An intermediate chamber  240  may also be provided behind the forward chamber  210 , as shown in  FIG. 3 . The walls or surfaces  246  of the intermediate chamber  240  may be planar (or conical) as shown in  FIG. 3  or curved inwardly, i.e., convex, as depicted in  FIG. 4 , and the entire chamber  240  or a portion of the chamber  240  may exhibit this shape. In either case, the intermediate chamber  240  is oriented such that the narrow end  242  of the intermediate chamber  240  is closer to the tip  12 ; the wide end  244  of the chamber  240  is closer to the faceplate  20 . Again, a stopper  310  can be provided for the receiver tube. In this instance, it would be located in the intermediate chamber  240 , closer to the receiver  100  and further from the tip  12  of the shell  10 .  
         [0024]     If desired, instead of an immediate transition from the intermediate chamber  240  to the forward chamber  210 , an interconnecting channel  250  (see  FIG. 3  or  4 ) can be provided between the intermediate chamber  240  and the forward chamber  210 . In this arrangement, the receiver tube  300  passes through the intermediate chamber  240 , the interconnecting channel  250 , and then the forward chamber  210 . Alternatively, the intersection between the two chambers  210  and  240  can be abrupt, with no interconnecting passage.  
         [0025]     Depending on the outer shape of the shell  10 , the forward and intermediate chambers  210  and  240  may be collinear, as illustrated in  FIG. 5  and evidenced by the relatively straight receiver tube  300  (note the dashed line denoting the axis of the receiver  100  and the receiver tube  300 ), or they may lie on different axes as illustrated in  FIGS. 3 and 4  (note the dashed lines representing the axes of the two chambers).  
         [0026]     To accommodate the particular shape of the chambers, the stoppers  310  illustrated in  FIGS. 1-5  conform to the taper of the walls ( 216  or  246 ). As an alternative, a recess  248  can be provided for the stopper  312  as shown in  FIG. 6  at the narrow end  242  of the intermediate chamber  240 . Here, the recess  248  provides a conforming receptacle having a generally rectangular profile for a stopper  312  having a similarly non-tapered profile, such as a torus. As an additional refinement, the stopper may assume the form of a polyhedron, such as the stopper  314  illustrated in  FIG. 7 . Here, the walls  246  of the shell  10  are planar, defining four of five surfaces of a pentahedral chamber. In this particular case, the stopper  314  must be positioned in one of four possible orientations (i.e., at 0, 90, 180, or 270 degrees), radially orienting the receiver  100  (not shown in this view). Alternatively or in addition, a locating spline and keyway (shown collectively in  FIG. 7  in phantom as element  320  and described in U.S. application Ser. No. 10/218,013) could be provided on the receiver tube  300  and the interconnecting channel  250 , respectively, or on the stopper  312  and the recess  248  of  FIG. 6 , respectively.  
         [0027]     In  FIGS. 1-6 , the chambers  210  and  240  assume a single shape or contour, whether the walls are planar or convex surfaces. In a particularly small hearing instrument, there may be a desire to move the receiver  100  as close as possible to the tip  12  to maximize the use of space within the shell interior  200 . This may be achieved by flaring a portion of the walls or surfaces of the chamber, either in the forward chamber  210  or the intermediate chamber  240 , or both, creating a second angular profile or contour, whether planar, conical, or convex, within the same chamber.  
         [0028]     In  FIG. 8 , the angular orientation of the walls  216  at the narrow end  212  of the chamber  210  with respect to the axis of the chamber  210  defines one angle or a first angular contour  218 , while the portion at the wide end  214  of the chamber  210  defines a greater angle or a second angular contour  220  (note the dashed lines). Similarly, in  FIG. 9 , distinct inwardly curved (or, convex or hyperboloidal) contours or surfaces  222  and  224 , exhibiting different degrees of curvature relative to the axis of the chamber  210 , are illustrated for the narrow and wide ends  212  and  214  of the chamber  210 , respectively (again, note the dashed lines).  
         [0029]     If desired, planar, conical, and convex walls could be used in combination for the multiple contours, e.g., one planar and one convex, or planar and conical, or convex and conical, within the same chamber. Additionally, the chambers  210  and  240  could be divided into more than two sections, such that there are three or more contours or shapes from one end of the chamber ( 210  or  240 ) to the other. Also, the walls or surfaces within the same section of the chamber could be a combination of planar and convex contours. Finally, a shell could have more than two chambers, e.g., a very long shell.  
         [0030]     Assembly of the shells is enhanced with the configurations of  FIGS. 1-9 . In each case, the free end  302  of the receiver tube  300 , i.e., the end not attached to the receiver  100 , is inserted into the intermediate chamber  240 , if one has been provided, through an interconnecting channel  250  if present, and then into the forward chamber  210 , and towards the receiver tube hole  14 , and then through the receiver tube hole  14 . The contours of the walls or surfaces in the forward and intermediate chambers  210  and  240  guide the free end  302  of the receiver tube  300  through the chamber  200 , without fear of having the end  302  catch against the inside of the shell  10 .  
         [0031]     The receiver tube  300  and the stoppers  310  and  312  may be fabricated from a synthetic material such as an elastomer or any other suitable material. One such elastomer is marketed by DuPont Dow Elastomers, L.L.C. under the trademark Viton.

Technology Classification (CPC): 7