Patent Publication Number: US-8973703-B2

Title: High retention aural transmission device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to, and is a continuation of U.S. patent application Ser. No. 13/562,809, entitled “High Retention Aural Transmission Device,” filed 07/31/2012 by Matthew Barnes, the entire disclosure of which is incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     Various embodiments relate generally to aural canal inserts. 
     SUMMARY 
     Apparatus and associated methods may relate to a unitary body having a hardness of between 20 and 35 according to the Japanese Industrial Standards (JIS) and adapted to be removably inserted into the canal  10  of an ear. In an illustrative example, the body includes a central portion between an adapter portion disposed at the proximal end of the body to couple an audio signal from an audio signal source to the central lumen. The retention portion may be disposed at a distal end of the body along a distal end axis. When inserted in the ear canal, the retention portion may be adapted to engage the canal wall between a prominence and the eardrum membrane with comfort for extended periods of time, including during physical activities, without falling out of the ear. Some embodiments by be packaged as a kit containing pairs in a range of predetermined sizes. 
     Various embodiments may achieve one or more advantages. For example, some embodiments may provide a range of predetermined sizes to allow a user to try on various sizes to determine which ones are small enough to be comfortable, yet long enough to substantially retain the HRATD in the ear canal without falling out, e.g., during physical activity. Various embodiments may have a standard aural insert with a hardness within a range that permits extended use with substantially improved discomfort, and a shape to promote retention in the ear canal during periods of extended use. Some embodiments may provide high retention performance and substantial comfort during vigorous physical activity, such as snow boarding, for example. Some embodiments may advantageously promote high retention and significant comfort in the ear canal for a statistical majority of a human population at one of a plurality of predetermined combination of dimensioned shapes within a range of sizes. Various embodiments may provide adapters compatible for coupling to a variety of industry standard audio sources (e.g., earphone speakers). In various implementations, a user may enjoy an aural transmission device with the retention and comfort of a custom-fitted device for far less investment in time and expense than is typically required to obtain a comparable wax mold from an audiologist. 
     The details of various embodiments are set forth in the accompanying drawings and the description below. Other features and advantages will be apparent from the description and drawings, and from the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts anatomical side and cross-sectional views of a human left ear. 
         FIG. 2  depicts an exemplary kit of high retention aural transmission devices (HRATDs) of a range of sizes for comfortable fit with high retention when inserted into a human ear while coupling to an audio source. 
         FIG. 3  depicts a side view of an exemplary HRATD. 
         FIGS. 4-5  depict exemplary cross-sectional views of the HRATD of  FIG. 3 . 
         FIG. 6  depicts a table of exemplary dimensions for a range of sizes of the HRATD of  FIGS. 3-5 . 
         FIG. 7  depicts back, side and front views, respectively, of left and right HRATDs, according to one exemplary embodiment. 
         FIG. 8  depicts an exemplary left and right pair of HRATDs adapted to be releasably coupled to an audio source. 
         FIG. 9  depicts a cross-sectional view of an exemplary HRATD showing a central lumen there through. 
     
    
    
     Like reference symbols in the various drawings indicate like elements. 
     DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
       FIG. 1  depicts anatomical side and cross-sectional views of an exemplary human left ear. By way of background for anatomical references made herein,  FIG. 1  depicts a prior art model of a human ear canal  10  that leads to an interior eardrum membrane  12 . Around the exterior of the ear canal  10 , the figure depicts a tragus  14 , anti-tragus  16 , incisura  18 , concha  20 , pinna  22 , and pendant lobe  24 . In the interior cross-section view, taken along section line A′-A′, the figure depicts an outer end  28  of the canal  10 , a prominence  30 , skull portion  32 , a tip  34  of the prominence  30 , a generally concave surface portion  36 , pain sensitive cavity  38 , and a region  60  between the prominence  30  and the eardrum membrane  12 . Further description may be found with reference to  FIGS. 1-2  of U.S. Pat. No. 5,298,692 to Ikeda, et al., the entire disclosure of which is incorporated herein by reference. 
       FIG. 2  depicts an exemplary kit of high retention aural transmission devices (HRATDs) of a range of sizes for comfortable fit with high retention when inserted into a human ear while coupling to an audio source. In the depicted example, a kit  200  includes a sealable package  205  that encloses 4 pairs of HRATDs  210   a - 210   d . Each pair of the HRATDs  210   a - 210   d  includes an exemplary HRATD adapter for insertion and retention in the left and right ears, respectively. Each of the pairs  210   a - 201   d,  respectively, is sized to be comfortably retained in a different size ear canal, such as the ear canal  10  described with reference to  FIG. 1 . Examples of dimensions for each size of ear are described in further detail with reference to  FIGS. 3-7  and  9 . 
     For purposes of an illustrative example, a left HRATD  215  is depicted in further detail in a detail view  220 . As depicted, the HRATD  215  couples to an audio output device  225 . The depicted audio output device  225  is a wireless receiver (e.g., Bluetooth), but may be wired or wirelessly connected to receive audio information from a remote signal source. The HRATD  215  mechanically couples to the audio source by receiving a male interface to a female adapter. The HRATD  215  is configured to be inserted into a right ear  230 . It may be appreciated that the corresponding size right HRATD  215  in the kit  200  may be similarly coupled to an audio source and inserted into the opposing left ear. 
     By providing a range of sizes for the pairs  210   a - 210   d,  the kit  200  may advantageously provide a user the ability to rapidly determine a user-preferred combination of comfortable fit and adequate retention in the ear. As will be described in further detail with reference to  FIGS. 3-7  and  9 , for example, a user may try on various sizes to determine which ones are small enough to be comfortable, yet of adequate dimensions to substantially retain the HRATD  215  in the ear canal  10  without falling out, e.g., during physical activity. 
     As seen in detail view  235 , the HRATD  215  is formed as a unitary body that includes an adapter portion  240 , a central portion  245 , and a retention portion  250 . The HRATD  215  further includes a central lumen  255  extending from a proximal end of the body to a distal end of the body to provide fluid communication from a region external to the canal  10 . 
     The HRATD  215  may be formed as a unitary body having a hardness of between 20 and 35 according to the Japanese Industrial Standards (JIS) and adapted to be removably inserted into the canal  10  of an ear. The central portion  245  is disposed along the length of the body between the adapter portion  240  and the retention portion  250 . The adapter portion  240  is disposed at the proximal end of the body to couple an audio signal from an audio signal source to the central lumen. The retention portion  245  is disposed at a distal end of the body along a distal end axis. When inserted in the ear canal, the retention portion  245  may be adapted to engage the canal wall between a prominence  30  and the eardrum membrane  12 . 
     In an illustrative example, a properly fitted distal end may extend at least 5 millimeters into the canal  10  past a tip  34  of the prominence  30 . This extension past the prominence  30 , in combination with a reduced hardness, may, in various examples, substantially improve retention performance without significantly sacrificing comfort. 
       FIG. 3  depicts a side view of an exemplary HRATD. In the depicted example, an HRATD  300  includes a unitary body having an adapter portion  305 , a central portion  310 , and a retention portion  315 . A proximal axis  320  is centrally located within an aperture in the adapter portion  305 , the aperture in the adapter portion being in fluid communication with an aperture in the retention portion  315  via a central lumen  325  that extends through the regions  305 - 315 . A distal axis  330  is centrally located through the aperture in the retention region. 
     The lumen  325  in the adapter region  305  is approximately symmetrical about the proximal axis  320 . The lumen  325  in the retention region  315  is approximately symmetrical about the distal axis  330 . The central lumen  325  between the adapter region  305  and the retention region  315  generally follows the curvature of the central region  310 . 
       FIGS. 4 and 5  represent cross-sectional views taken through a distal axis point  350  and a proximal axis point  352 , respectively. 
     In the side view of  FIG. 3 , the upper surface of the HRATD  300  is concave upward, with a valley  354  (low point). The cross-section of  FIG. 5  passes through valley  354  and proximal axis point  352 , and extends down to a generally upward sloping bottom surface  356  of HRATD  300 . 
     In the side view of  FIG. 3 , the surface of the HRATD  300  terminates in a distal end  358 . The cross-section of  FIG. 4  passes through distal end  358  and distal axis point  350 , and extends down to the bottom surface  356 . 
     A dimension “c” is defined as the distance between planes of cross-section for  FIGS. 4 and 5 . By way of example, the dimension “c” may be from about 4 to about 6 mm. 
       FIGS. 4-5  depict exemplary cross-sectional views of the HRATD of  FIG. 3 . In  FIG. 4 , a dimension “b” in this example is defined as the distance between the distal end  358  and the bottom surface  356  along the distal axis  330 . A dimension “a” is defined in this example as a width of the body in the retention region  315 . In various examples, the “b” dimension may be at least about 10 mm. 
     In  FIG. 5 , a dimension “b′” in this example is defined as the distance between the valley  354  and the bottom surface  356  in the cross-section of  FIG. 5 . A dimension “a′” is defined in this example as a width of the body in the adapter region  305 , as indicated in the cross-section of  FIG. 5 . 
       FIG. 6  depicts a table of exemplary dimensions for a range of sizes of the HRATD of  FIGS. 3-5 . As depicted, in various embodiments, the least difference in any size between b to b′ is 5 mm, and the greatest insertion depth difference (b-b′) is 7.4 mm. In some implementations, such as where the valley point  354  is in intimate contact with the prominence tip  34 , the insertion depth difference may, for example, approximate the distance for a plane tangential to the prominence tip  34  to the distal end  358 . 
     In various embodiments, the insertion depth difference (b-b′) may preferably be about 5.0, 5.2, 5.4, 5.6, 5.8, 6.0, 6.2, 6.4, 6.6, 6.8, 7.0. 7.2, or about 7.4. In some implementations, the insertion depth difference may be between 4 mm and 10 mm, such as between about 5 and about 8 mm. 
     In various embodiments, the increased insertion depth achieved past the prominence tip  34  may advantageously improve retention. To improve comfort with increased insertion depth, various embodiments may further provide for a reduced hardness of less than 35, such as between about 20 up to 35, such as for example, about 25 to about 33, or preferably about 30 on the JIS (Japanese Industrial Standard). In some embodiments the hardness may be approximately 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, or about 35. 
       FIG. 7  depicts back, side and front views, respectively, of left and right HRATDs, according to one exemplary embodiment. 
     In the depicted example, a left HRATD  705   a  and a right HRATD  705   b  are shown in side views. An overall maximum height is 15.6 mm, a maximum height of the adapter region is 9.8 mm, and height taken along the cross section through the valley point is 6 mm. A linear distance at the closest points on a flared flange of the adapter region to a distal end in the retention region is 6.5 mm. A width at the distal end is 4.8 mm, and overall width is 11.7 mm, in this example. 
     In the depicted example, a left HRATD  710   a  and a right HRATD  710   b  are shown in back views. An overall maximum width of the flared flange of the adapter region is 13.4 mm, in this example. 
     In the depicted example, a left HRATD  715   a  and a right HRATD  715   b  are shown in front views. The dimensions are as given above. 
       FIG. 8  depicts an exemplary left and right pair of HRATDs adapted to be releasably coupled to an audio source. In the depicted embodiment, a pair  800  of HRATDs  805   a ,  805   b.  The HRATDs include an adapter region  810  that provides a female adapter for coupling to an industry standard headphone device  815 , which is commercially available, for example, from Apple, Inc. of California. The headphone device supplies audio signals that couple through the central lumen of the HRATDs  805  and are thus delivered efficiently through to a distal end  820  of the HRATD. The improved retention features of the HRATD may advantageously promote the secure coupling of the audio source, e.g., headphone device  815 , in audio communication with the user&#39;s ear canal  10 . 
       FIG. 9  depicts a cross-sectional view of an exemplary HRATD showing a central lumen there through. In this example, an HRATD  900  includes a unitary body  905  that defines a central lumen  910  through an adapter portion  915 , a central portion  920 , and a retention portion  925 , with a substantially concave portion including a valley point  930 . 
     In the adapter portion  915  of this example, a proximal end of the lumen  910  includes a first aperture  935  having a depth of about 1.5 mm and an inner diameter of about 5.7 mm, a duct  940  having a depth of about 1.5 mm and an inner diameter of about 2.8 mm, a second aperture  945  having a depth of about 1.5 mm and an inner diameter of about 5.7 mm, and a distal lumen portion  950  having a depth of about 1.5 mm and an inner diameter that monotonically decreases from about 5.7 mm to about 3.0 mm. 
     Although various embodiments have been described with reference to the Figures, other embodiments are possible. For example, aural retention devices may, in some embodiments, be adapted to be comfortably retained in the ear canal of another species, such as a dog, for example. Embodiments may be adapted for non-human ear canals, depending, in part, on the curvature and sensitivity to pain of the ear canal of some species or breeds of animals. 
     Some implementations may be formed without a sound transmission lumen. For example, some embodiments may serve as ear plugs to protect sensitive ear components from damage due to loud sounds. In such embodiments, the shapes described with reference to the figures may be substantially unchanged, but without the lumen. In some implementations, a sound-dampening filler may be substituted for the lumen. For example, a viscous liquid or granular filler (e.g., sand) or fiber (e.g., cotton) may be substituted in place of the lumen or other spaces or voids interior to the body of the device. 
     In a kit of HRATDs of various sizes, the hardness of each pair may be a function of size. For example, hardness may be the same or decrease, based upon material selection or formation, as the size increases. Accordingly, such embodiments may be substantially more compliant with increasing size within a given kit having a distribution of sizes contained therein. 
     Although some embodiments may be sold as kits of prefabricated sizes, some embodiments may be sold in pairs or individual left or right HRATDs, for example. In an illustrative example, a user who has already identified a desired size may directly purchase a selected size. In some embodiments, the user may select a preferred dimension of a, a′, b, b′, and c according to a predetermined and/or prefabricated. Some embodiments may be mass produced. 
     By way of example and not limitation, various embodiments may be formed, for example, materials such as silicone rubber, elastomers, polymers, medical grade silicones, or such materials in combination. Some implementations may be molded using various techniques (e.g., injection molding, vulcanization). 
     In various kit embodiments, the number of pairs included may include, for example, at least 3, such as 4, 5, 6, 7, 8, 9, or 10 pairs. The number of different combinations of dimensional sizes included in a kit may be, for example, at least 2, such as 3, 4, 5, 6, 7, 8, 9, or 10. 
     Although various embodiments have been depicted in the figures as having a substantially 90 degree bend in the central region between the adapter region and the retention region, other angles are possible. For example, some embodiments may be formed with an elbow angle of between about 70 to 130 degrees, for example, such as between about 80 and about 120 degrees, or preferably between about 85 and 115 degrees, for example. 
     Some embodiments may be formed to have differentiated hardnesses in different regions. For example, different hardnesses may be employed in the adapter region for coupling to a sound device than the distal end in the retention region 
     Within a kit, the hardness characteristics of each embodiment may be substantially similar within one kit. Within a single device, the outside hardness may be between 20-35, for example. In some examples, the interior in the adapter region  915  may be of an elevated hardness. The interior surfaces may have a hardness in the range about 40-60 to retain the connection to the interior surfaces in the  935 ,  940 ,  945  to hold the device in  FIG. 9 . The adapter region  810  in the embodiment depicted, for example, in  FIG. 8 , may be formed substantially throughout from a material having a hardness of about 30, for example, such as between about 20-35. 
     In various embodiments, a ratio k=b/a, and k′=b′/a′. In various examples, k is at least about 1.4 or more. The ratio k may be advantageously increased to improve retention by interference in the wall past the prominence tip  34 , for example. The bottom surface  356  may further, in some examples, interfere with the concave surface portion  36  and/or the valley point  354  may interfere with the prominence tip  34 . 
     In certain embodiments, apparatus and methods may involve aural retention devices for hearing aid devices, for example. 
     Various examples may include a pair of left and right HRATDs that are substantially mirror image shapes of each other, whereby the left and right are not interchangeable in the opposite ear. 
     Various embodiments are formed in a substantially elliptical shape in at least a portion of the distal, central, and/or proximal portions. In some embodiments, an elliptical form factor may advantageously stabilize against rotation within the ear canal. 
     In some implementations, a proximal portion, which may include the adapter portion, may include a flared flange, which may advantageously control or limit the insertion depth of the distal end within the canal. This may advantageously prevent insertion further than intended in the ear canal. 
     In an exemplary embodiment, a kit, such as the kit  200  of  FIG. 2  may include multiple pairs in multiple predetermined sizes selected to provide a number of insertion depth differences. 
     A number of implementations have been described. Nevertheless, it will be understood that various modification may be made. For example, advantageous results may be achieved if the steps of the disclosed techniques were performed in a different sequence, or if components of the disclosed systems were combined in a different manner, or if the components were supplemented with other components. Not all drawings are necessarily to scale, and proportions may be exaggerated for illustration purposes. Accordingly, other implementations are within the scope of the following claims.