Abstract:
A hearing aid instrument of the in-the-ear type (and preferably CIC) provides a plate member with electronic hearing aid components mounted thereto. The plate member is preferably of a harder material such as hard plastic. A soft polymeric body is bonded to the plate member and encapsulates preferably a plurality of the electronic hearing aid components. The body is soft and is shaped to conform to the ear canal of the user. The soft polymeric body and encapsulated electronic hearing aid components define a soft structure compliant to the ear canal during use and that is substantially solid and free of void spaces between at least some of the components and the ear canal. This combination of soft compliant structure and encapsulated electronic hearing aid components addresses problems of peripheral leakage, poor fit, pivotal displacement that occurs with jaw motion and internal cross talk of components housed in prior art hollow type hearing aids.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is a continuation-in-part of co-pending U.S. patent application Ser. No. 10/784,534, filed 23 Feb. 2004 (U.S. Pat. No. 7,217,335), which is a continuation-in-part of co-pending U.S. patent application Ser. No. 09/855,095, filed 14 May 2001 (now U.S. Pat. No. 6,695,943), which is a continuation-in-part of co-pending U.S. patent application Ser. No. 09/311,156, filed 13 May 1999 (now U.S. Pat. No. 6,354,990), which is a continuation-in-part of co-pending U.S. patent application Ser. Nos. 09/181,539, 09/181,540 (now U.S. Pat. No. 6,432,247), 09/181,541 (now U.S. Pat. No. 6,438,244), 09/181,842 (now U.S. Pat. No. 6,254,526), 09/181,843 (now U.S. Pat. No. 6,434,248), 09/181,844 (now U.S. Pat. No. 6,228,020) and 09/181,845 (now U.S. Pat. No. 6,473,512), all filed 28 Oct. 1998, which are continuations-in-part of U.S. patent application Ser. No. 09/084,864, filed 26 May 1998 (now U.S. Pat. No. 6,022,311). Priority of each of these patent applications is hereby claimed.  
         [0002]     This is also a continuation-in-part of co-pending U.S. patent application Ser. No. 10/097,540, filed 11 Mar. 2002, (now U.S. Pat. No. 6,761,789), which is a divisional of U.S. patent application Ser. No. 09/311,156 (now U.S. Pat. No. 6,354,990).  
         [0003]     This is also a continuation-in-part of co-pending U.S. patent application Ser. No. 10/790,623, filed 1 Mar. 2004,  
         [0004]     Priority of U.S. Provisional Patent Application Ser. No. 60/456,057, filed 20 Mar. 2003, incorporated herein by reference, is hereby claimed.  
         [0005]     Priority of U.S. Provisional Patent Application Ser. No. 60/450,898, filed 28 Feb. 2003, incorporated herein by reference, is hereby claimed.  
         [0006]     Priority of U.S. Provisional Patent Application Ser. No. 60/203,983, filed 12 May 2000, incorporated herein by reference, is hereby claimed.  
         [0007]     Priority of U.S. Provisional Patent Application Ser. No. 60/068,036, filed 18 Dec. 1997, incorporated herein by reference, is hereby claimed.  
         [0008]     Each of the patent applications and patents mentioned herein are incorporated herein by reference. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0009]     Not applicable  
       REFERENCE TO A “MICROFICHE APPENDIX” 
       [0010]     Not applicable  
       BACKGROUND OF THE INVENTION  
       [0011]     1. Field of the Invention  
         [0012]     The present invention relates to hearing aids and more particularly to an improved hearing aid and its method of manufacture. More particularly, the present invention provides an improved method for constructing a hearing aid combining a mounting member (for example, a receptacle or face plate) with a soft polymeric body that is joined to the mounting member and which encapsulates one or more of the electronic hearing aid components of the apparatus, the soft polymeric body being sized and shaped to conform to the user&#39;s ear canal during use. In one form, a soft polymeric material is used as the face plate.  
         [0013]     2. General Background of the Invention  
         [0014]     The hearing industry has realized major strides in the development of high-fidelity, high-performance products, the most recent of which is digital signal processing technology. Hearing care professionals expected those advancements to solve the shortcomings of traditional amplification, and to push the market forward. Those expectations have not been fully realized. While these developments have solved many of the problems associated with traditional electronic design and steadily gained market share, they have not fostered overall market growth.  
         [0015]     The issues of early acoustic feedback, less than optimum fidelity and intermodulation of the frequency response cannot be completely resolved by electronic manipulation of the signal by either analog or digital means.  
         [0016]     Historically, custom-molded ear worn hearing instruments have been limited to an “acrylic pour” process as the means of the construction. With the advent of miniaturization and technological advancement of computer chip programming, the ear-worn instruments have become smaller and are positioned into the bony portion of the ear canal, commonly referred to as “deep insertion technology.” 
         [0017]     Developments outside the hearing industry have culminated in a new level of micro-miniaturization of electronic components for industry applications. Consequently, advanced signal processing can be housed in less space than was required for traditional electro-acoustic components.  
         [0018]     With the development of programmable hearing aids, using either analog or digital signal processing, custom electronic design has shifted from the manufacturing level to the clinical level. The clinician can now customize the electro-acoustic response via software. It is no longer necessary for the device to be returned to the manufacturer for hardware changes to arrive at the desired electro-acoustic response. However, it is still often necessary to return the device for shell modifications.  
         [0019]     In direct contrast to electronic advances within the industry, little or no advancement has been realized in custom prosthetic design. Since the late 1960&#39;s, when the custom in-the-ear hearing aid was developed, materials and construction techniques remained virtually unchanged. These materials and techniques were adopted from the dental industry, whereby the customized housing-commonly called a “shell” was constructed using acrylic of 90 point Durometer Hardness Shore D. This construction process provided the structure and the strength of material necessary to protect the electronics.  
         [0020]     At the time the acrylic shell was developed, hearing instruments were worn in the relatively forgiving cartilaginous portion of the ear canal. Micro-miniaturization of electronic components, combined with increased consumer demand for a cosmetically acceptable device, has shifted the placement of the hearing aid toward the bony portion of the ear canal.  
         [0021]     The bony portion of the canal is extremely sensitive and intolerant of an acrylic shell when that shell is over sized due to standard waxing procedures or is in contact with the canal wall beyond the second anatomical bend. Rigid acrylic that does not compress must pivot in reaction to jaw or head movement, thereby changing the direction of the receiver yielding a distorted acoustic response. In addition, the pivot action causes displacement of the device resulting in unwanted acoustic feedback. This problem has necessitated countless shell modifications, thereby compromising the precision approach of the original dental technology. Many such devices require some modification by the manufacturer. Most manufacturers can expect a high percentage of returns for modification or repair within the first year. Consequently, CIC (completely in canal) shell design has been reduced to more of a craft than a science. Although the recent introduction of the ultra-violet curing process has produced a stronger, thinner shell, the overall Shore Hardness remained unchanged.  
         [0022]     The current trend for custom hearing aid placement is to position the instrument toward the bony portion of the ear canal. The ear canal can be defined as the area extending from the concha to the tympanic membrane. It is important to note that the structure of this canal consists of elastic cartilage laterally, and porous bone medially. The cartilaginous portion constitutes the outer one third of the ear canal. The medial two-thirds of the ear canal is osseous or bony. The skin of the osseous canal, measuring only about 0.2 mm in thickness, is much thinner than that of the cartilaginous canal, which is 0.5 to 1 mm in thickness. The difference in thickness directly corresponds to the presence of apocrine (ceruminous) and sebaceous glands found only in the fibrocartilaginous area of the canal. Thus, this thin-skinned thinly-lined area of the bony canal is extremely sensitive to any hard foreign body, such as an acrylic hearing instrument.  
         [0023]     Exacerbating the issue of placement of a hard foreign body into the osseous area of the ear canal is the ear canal&#39;s dynamic nature. It is geometrically altered by temporomandibular joint action and by changes in head position. This causes elliptical elongation (widening) of the ear canal. These alterations in canal shape vary widely from person to person. Canal motion makes it very difficult to achieve a comfortable, true acoustic seal with hard acrylic material. When the instrument is displaced by mandibular motion, a leakage or “slit leak” creates an open loop between the receiver and the microphone and relates directly to an electroacoustic distortion commonly known as feedback. Peripheral acoustic leakage is a complex resonator made up of many transient resonant cavities. These cavities are transient because they change with jaw motion as a function of time, resulting in impedance changes in the ear canal. These transients compromise the electroacoustic performance.  
         [0024]     The properties of hard acrylic have limitations that require modification to the hard shell exterior to accommodate anatomical variants and the dynamic nature of the ear canal. The shell must be buffed and polished until comfort is acceptable. The peripheral acoustic leakage caused by these modifications results in acoustic feedback before sufficient amplification can be attained.  
         [0025]     Hollow shells used in today&#39;s hearing aid designs create internal or mechanical feedback pathways unique to each device. The resulting feedback requires electronic modifications to “tweak” the product to a compromised performance or a “pseudo-perfection”. With the industry&#39;s efforts to facilitate the fine-tuning of hearing instruments for desired acoustic performance, programmable devices were developed. The intent was to reduce the degree of compromise, but by their improved frequency spectrum the incidence of feedback was heightened. As a result, the industry still falls well short of an audiological optimum.  
         [0026]     A few manufacturers have attempted all-soft, hollow shells as alternatives to acrylic, hollow shells. Unfortunately, soft vinyl materials shrink, discolor, and harden after a relatively short period of wear. Polyurethane has proven to provide a better acoustic seal than polyvinyl, but has an even shorter wear life (approximately three months). Silicones have a long wear life but are difficult to bond with plastics such as acrylic, a necessary process for the construction of custom hearing instruments. To date, acrylic has proven to be the only material with long term structural integrity. The fact remains, however, that the entire ear is a dynamic acoustic environment and is ill-served by a rigid material such as acrylic. Also, the acrylic hearing aids typically need to be returned to the manufacturer for major shell modifications.  
         [0027]     The following references are all incorporated herein by reference:  
         [0028]     U.S. Pat. Nos. 4,051,330; 4,375,016; 4,607,720; 4,716,985; 4,811,402; 4,870,688; 4,880,076; 4,937,876; 5,002,151; 5,068,902; 5,185,802; 5,201,007; 5,259,032; 5,530,763; 5,430,801; 5,500,902; and 5,659,621.  
         [0029]     A Japanese reference that discusses a hearing aid that features a thin wall soft shell is the Takanishi patent application number 1989-238198.  
         [0030]     Also of interest and incorporated herein by reference are published Japanese patent application no. JA61-238198, the articles from December 1997 Journal of American Academy of Audiology, and Staab, Wayne J. and Barry Finlay, “A fitting rationale for deep fitting canal hearing instruments”, Hearing Instruments, Vol. 42, No. 1, 1991, pp. 7-10, 48.  
       BRIEF SUMMARY OF THE INVENTION  
       [0031]     The present invention provides a method and material for the construction of a soft hearing instrument that is solid (i.e. eliminates void spaces). This instrument includes a soft body portion that is truly soft, comprising an elastomer of about 3 to 55 durometer Shore A and preferably 10-35 durometer Shore A. This product is unique in that it is solid, with the electronic components actually encapsulated or embedded within the soft fill material. The fill material can be a Dow Corning® MDX-4-4210 silicone or a silicone polymer distributed by Factor II, Inc. of Lakeside, Ariz., designated as product name 588A, 588B, 588V.  
         [0032]     The present invention provides a method that can replace traditional acrylic shell construction. Unlike the shell construction process, the ear impression is not modified, built up, or waxed. With the elimination of these steps, a more faithful reproduction of the ear impression is accomplished. With the present invention, the manufacturer should be able to produce a hearing aid body which will not need to be returned as frequently for modification as with present hard acrylic hearing aid bodies.  
         [0033]     The apparatus of the present invention is virtually impervious to the discoloration, cracking, and hardening experienced with polyvinyls and polyurethanes.  
         [0034]     The hearing aid of the present invention provides a greater range of gain before feedback occurs.  
         [0035]     The outer surface of the body of the present invention is preferably non-absorbent and virtually impervious to cerumen.  
         [0036]     As used herein, “in the ear hearing aids” includes all hearing aids which have all of the electronics positioned in the ear, and thus includes hearing aid styles ranging from full concha to CIC (completely in the canal) hearing aid styles. An embodiment of the present invention shown in the drawings is a CIC hearing aid style. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0037]     For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein:  
         [0038]      FIG. 1  is a sectional elevational view of a user&#39;s hearing area to show the anatomy thereof;  
         [0039]      FIG. 2  is a sectional elevational view of a user&#39;s ear canal showing placement of a dam and mold material as part of the method of the present invention;  
         [0040]      FIG. 3  is a perspective view of the form portion used with an embodiment of the method of the present invention;  
         [0041]      FIG. 4  is a perspective view illustrating shaping of the form as part of the method of the present invention;  
         [0042]      FIG. 5  is a perspective view illustrating a dipping of the form into a vessel carrying material for making the female mold as part of the method of the present invention;  
         [0043]      FIG. 6  is a perspective view illustrating a coating of the form with the female mold as part of the method of the present invention;  
         [0044]      FIG. 7  is a partial elevational view of an embodiment of the apparatus of the present invention illustrating the mounting member and the plurality of the electronic hearing aid components;  
         [0045]      FIG. 7A  is a cross-sectional view taken along the line  7 A- 7 A in  FIG. 7 ;  
         [0046]      FIG. 7B  is a partial view showing the portion indicated in  FIG. 7  as  7 B;  
         [0047]      FIG. 8  is a elevational view of the lateral side of the mounting member taken along lines  8 - 8  of  FIG. 7 ;  
         [0048]      FIG. 9  is a perspective view illustrating the method step of joining the female mold to the mounting member at the medial side thereof;  
         [0049]      FIG. 10  is a perspective view of an embodiment of the apparatus of the present invention and showing the method of the present invention after the joining of the female mold and mounting member;  
         [0050]      FIG. 11  is a perspective view illustrating the method step of adding filler material to the interior of the female mold and encapsulating electronic hearing aid component portions of the apparatus;  
         [0051]      FIG. 12  is a perspective view illustrating removal of the female mold after the filler material has set and encapsulating the electronic hearing aid components;  
         [0052]      FIG. 13  is a perspective of an embodiment of the apparatus of the present invention and the method of the present invention illustrating removal of excess plate and tube material from the mounting member;  
         [0053]      FIG. 14  is a perspective view of an embodiment of the apparatus of the present invention;  
         [0054]      FIG. 15  is an elevational view of an embodiment of the apparatus of the present invention;  
         [0055]      FIG. 16  is an end view of an embodiment of the apparatus of the present invention taken along lines  16 - 16  of  FIG. 15 ;  
         [0056]      FIG. 17  is a top view of an embodiment of the apparatus of the present invention taken along lines  17 - 17  of  FIG. 15 ;  
         [0057]      FIG. 18  is a graphical representation of a comparison of real ear occlusion gain for the present invention versus a hard shell, hollow-type instrument;  
         [0058]      FIG. 19  is a graphical representation showing a comparison of real ear aided gain obtained before acoustic feedback, comparing the present invention with a hard shell, hollow-type instrument;  
         [0059]      FIG. 20  is a perspective view illustrating an alternate method of the present invention, namely the initial step of forming the female mold;  
         [0060]      FIGS. 21-22  show the alternate method of the present invention including a heating of the vacuum forming film material;  
         [0061]      FIG. 23  is a perspective view of the alternate method of the present invention shown during vacuum forming;  
         [0062]      FIG. 24  is a perspective view of the alternate method of the present invention showing the female mold as part of a vacuum formed sheet;  
         [0063]      FIG. 25  is a perspective view of the alternate method of the present invention showing removal of the female mold from the vacuum molded sheet;  
         [0064]      FIG. 26  is a perspective view of the method of the present invention showing the female mold after forming using the method steps of  FIGS. 23-25 ;  
         [0065]      FIG. 27  is a partial perspective view showing a second alternate embodiment of the method of the present invention, showing the coating of the vent tube;  
         [0066]      FIG. 28  is a partial perspective view showing a second alternate embodiment of the method of the present invention, showing removal of the mold to provide a soft solid body with contained vent tube and insert;  
         [0067]      FIG. 29  is a partial perspective view showing a second alternate embodiment of the method of the present invention, illustrating an insertion of the hearing aid component assembly into the void space that was formed by removal of the insert;  
         [0068]      FIG. 30  is a perspective view that illustrates the second alternate embodiment of the method and apparatus of the present invention;  
         [0069]      FIG. 31  is a perspective view illustrating the second alternate embodiment of the method and apparatus of the present invention; and  
         [0070]      FIG. 32  is a perspective view illustrating the second alternate embodiment of the method and apparatus of the present invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0071]      FIGS. 1 and 2  show a user&#39;s ear  1  and anatomical parts of the ear. In  FIG. 1  there can be seen the external auditory canal  2 , ear canal wall  3 , auricle  4 , isthmus  5 , tympanic membrane  6 , middle ear  7  and inner ear  8 . In  FIG. 2 a  dam  9  such as a cotton dam or otoblock dam is positioned at the isthmus  5 . The dam  9  is used as a first step of an embodiment of the method of the present invention wherein a form portion  11  or impression material is formed of silicone, methylmethacrylate or alginate. The form  11  is formed in between dam  9  and auricle  4  as shown in  FIG. 2 .  
         [0072]     During the method step of making form  11 , the form  11  conforms to all of the curvatures of the ear canal  3  so that an accurate form  11  is provided for making a female mold.  
         [0073]     The female mold  15  is shown in  FIGS. 6 and 9 - 12 . In  FIGS. 3 and 4 , the form  11  is shown after being removed from the ear  1  ( FIG. 3 ) and during a cutting of the form  11  using knives  12  to cut excess material that is designated as  13 ,  14  in  FIG. 4 . The form  11  is separated from excess material  13  and  14  at sagittal plane  16 . After the form  11  is trimmed in  FIG. 4 , a technician&#39;s hand  18  dips the form  11  into vessel  17  as schematically indicated by the arrow  20 . The vessel  17  includes a liquid material  21  that cures at room temperature, such as room temperature curing methacrylate (sold by Esschem). A clear material  21  can be used in the method step shown in  FIG. 5 .  
         [0074]     In  FIG. 6 , the technician&#39;s hand  18  has removed the form  11  so that a coating of material  21  cures at room temperature (or with an ultraviolet light process) to form female mold  15  on form  11 . After it cures, the female mold  15  is removed from form  11  for use as shown in  FIGS. 9 and 10  during assembly of the apparatus  10  of the present invention. The mold  15  can be a few millimeters in wall thickness (typically 1-3 mm).  
         [0075]     A number of electronic components are mounted to a mounting member  22  prior to use of the female mold  15 . Mounting member  22  provides a medial side  23  and lateral side  24 . The medial side  23  supports a number of hearing aid electronic components as shown in  FIGS. 7, 9 , and  10 . In  FIG. 7 , these hearing aid electronic components include commercially available hearing aid components including a microphone  25 , volume control, battery, socket or plug  28  for communicating with a computer, chip or micro processor circuit, wiring harness  38 , input capacitor, amplifier  34 , receiver/speaker  35 , and receiver tube  37 .  
         [0076]     In  FIG. 8 , the lateral side  24  of mounting member  22  shows the microphone  25 , battery compartment  26 , volume control  27 , programming socket  28  for communicating with a computer, silicone plug  54  (see  FIG. 9 ), and vent opening  29  that communicates with vent tube  30  (see  FIG. 10 ). In  FIG. 9 , battery  31  is shown housed in battery compartment  26 . The electronic hearing aid components also include a battery terminal  32 , voltage regulating capacitor  33  (see  FIG. 15 ), amplifier/microprocessor  34 , receiver  35  having speaker port  36 , and receiver tube  37 . A wiring harness  38  includes a plurality of wires that connect to various electronic components of the hearing aid device together. The wiring harness  38  includes a length of wires  39  that are arranged in an S or multiple curved pattern as shown in  FIG. 7 . This “S loop” configuration of wires  39  helps protect the integrity of the electronics when the hearing aid apparatus  10  is flexed as occurs during use because of its soft nature. Further, the S-loop wires  39  are preferably a 44 gauge five strand Litz wire (or magnet wire). The length of the S-loop wires  39  is preferably at least 1.5 times the distance between the terminals to the receiver (or microprocessor)  35  and the amplifier  34  terminals. These “S-Loop” wires  39  prevent excess tension or compression from being transmitted to the electronics during use (e.g. flexing, elongation, compression of hearing aid  10 ).  
         [0077]     Vent tube  30  is anchored to the mounting member  22  and preferably also to one of the electronic components at a position spaced away from the mounting member  22 . Vent tube  30  acts as a tensile load carrying member that carries tension so that the wiring harness  38  is substantially free of a tensile load that could damage the wiring harness  38 . Also, when vent tube  30  is anchored to one of the electronic components (such as receiver  35 ) at a position spaced away from the mounting member  22 , it may provide enough strain relief that it would not be necessary to coil wires  39  as shown (they could be straight instead).  
         [0078]     Something else could be used as a load carrying member, in place of vent tube  30  (in which case vent tube  30  would not necessarily be anchored to one of the electronic components (such as receiver  35 )) at a position spaced away from the mounting member  22 . For example, a monofilament cantilever  55  can be used to carry tension so that tension is not transmitted to wiring harness  38 . In  FIGS. 7, 7A , and  7 B the link  55  is anchored to plate  22  at opening  56 . Fastener  57  affixes to receiver tube  37  at large opening  59 . Monofilament cantilever  55  attaches to fastener  57  at smaller diameter opening  58 . Alternatively, vent tube  30  could be manufactured of a tensile material that carries tensile load. The vent tube  30  would then be anchored to plate  22  and fastener  57  as the tensile member.  
         [0079]     The monofilament cantilever  55  provides longitudinal stability to the body. It minimizes longitudinal displacement (stretching as well as compression) and thus acts as a longitudinal stabilizer (a longitudinal load carrying member). As described above the monofilament cantilever  55  can be used as an alternative embodiment.  
         [0080]     After the electronic components (sometimes designated generally in the drawings by the letter “E”) are assembled to the medial  23  side of mounting member  22 , female mold  15  is used to complete the method of construction of the present invention as shown in  FIG. 9-13 . In  FIG. 9 , the female mold  15  is placed over the electronic components “E” beginning with the distal end portion of receiver tube  37  and the distal end portion of vent tube  30  as indicated by arrows  40  in  FIG. 9 . A plurality of three openings  41 ,  42 ,  43  are provided at distal end  44  of female mold  15  as shown in  FIG. 9 . The proximal end  45  of female mold  15  provides an annular edge surface  19  that engages the medial  23  side of mounting member  22  as indicated by the dotted line  46  in  FIG. 9 .  
         [0081]     A joint is formed between annular edge surface  19  of female mold  15  and medial surface  23  of mounting member  22  at a position schematically indicated as dotted line  46  in  FIG. 9 , using the method of the present invention. The medial surface  23  of mounting member  22  is cleaned with a suitable solvent. Acetone can be used as a solvent in the case of a mounting plate  22  that is made of acrylic. The medial surface  23  of mounting member  22  is then painted with a primer using a swab or brush. The primer is allowed to dry. A bonding agent is then applied to the medial surface  23  of mounting member  22  and allowed to dry. The bonding agent or bonding enhancer can be product A-320 of Factor II, Inc. of Lakeside, Ariz., which is a member of the chemical family “silicone primer”.  
         [0082]     The female mold  15  is placed against the medial side  23  of mounting member  22 . A liquid acrylic is used to form an acrylic seam at the interface of annular edge surface  19  of female mold  15  and the medial side  23  of mounting member  22  (see  FIG. 10 ). As the female mold  15  is assembled to mounting member  22 , vent tube  30  passes through opening  41 . Receiver tube  37  passes through opening  42 . The opening  43  is then used for injection of filler material  50  (e.g. via needle  49 ) as shown by arrows  51 ,  52  in  FIG. 11 . During this process, temporary seal  47  holds the liquid filler material  50  within the interior  53  that is formed by female mold  15  and mounting member  22 . The filler material  50  can be a liquid during the injection step of  FIG. 11  so that it encapsulates at least the receiver/speaker electronic component  35  and preferably other components as well.  
         [0083]     In  FIG. 12 , the female mold  15  is removed after the material  50  has set. The mounting member  22  (which can be in the form of a circular, generally flat face plate) is then cut at the phantom line  46  that basically tracks the periphery of female mold  15  at annular edge surface  19  at proximal end  45  thereof. This cutting of the unused, unneeded part of mounting member  22  is shown in  FIG. 13 .  FIGS. 14-17  show the completed apparatus  10  of the present invention.  
         [0084]     The present invention provides a soft, yet solid hearing aid instrument that will provide a more appropriate environment for both the high fidelity performance of today&#39;s advanced circuitry and the dynamic ear canal.  
         [0085]     The present invention teaches a soft construction of at least the distal portion of the apparatus  10  so that at least the receiver/speaker is encapsulated with the soft material  50 . This construction results in a precise representation of the human ear canal, flex with jaw motion, and cushion for the embedded electronic components “E”.  
         [0086]      FIG. 18  demonstrates real ear occlusion gain (REOG) finding obtained from a wearer having a tortuous ear canal. The curve  101  represents the REOG of a hard shell, hollow type hearing aid instrument. The curve  102  represents the REOG of an instrument  10  made according to the method of the present invention. As can be seen in  FIG. 18 , the present invention instrument provided 20 dB more attenuation than did the hard shell, hollow hearing aid instrument represented by the curve  101 . Because of the sharp first directional bend of the wearer&#39;s ear canal, the hard shell instrument could not be inserted without modification. The apparatus  10  of the present invention was insertable without modification thereby yielding a tighter seal in the wearer&#39;s ear.  
         [0087]      FIG. 19  is a graphical representation that demonstrates real ear aided gain (REAG) findings obtained from a wearer having a tortuous ear canal. The curves shown ( 103 ,  104 ) were obtained from the instruments used to generate the finding shown in  FIG. 18 . Curve  103  represent REAG before feedback of the apparatus  10  of the present invention. Curve  104  demonstrates the REAG before feedback of a hard shell, hollow type hearing aid instrument of the prior art. As can be seen in  FIG. 19 , the instrument  10  of the present invention represented by curve  103  provided more gain across the frequencies. This REAG is inversely proportional to the amount of occlusion gain (REOG) or attenuation provided by the apparatus  10  of the present invention. It should be restated that, because of the sharp first directional bend of the wearer&#39;s ear canal, the hard shell, hollow type instrument of the prior art could not be inserted without being modified. The apparatus  10  of the present invention was insertable without modification, thus the present invention provides higher added gain values (REAG) when a more negative REOG can be achieved while maintaining comfort.  
         [0088]      FIGS. 20-25  show an alternate method for forming the female mold that is then used with the embodiment of  FIGS. 1-19 . The female mold is designated generally by the numeral  15 A in  FIG. 26  after forming and using the method steps shown in  FIGS. 20-25 . In  FIG. 20 , a vacuum mold apparatus  60  has a base  61  that supports a post  62  and heating element  63 . Base  61  contains a vacuum pump. Frame  64  can be pivotally mounted to base  61  at post  62 . Frame  64  provides opening  65 .  
         [0089]     A matrix  66  of small openings is provided at the upper portion of base  61 . Matrix  66  of openings communicates with the vacuum pump in base  61 . In  FIG. 21 , the sheet of film material  67  is placed into and raised with frame  64  as indicated by arrows  68  in  FIG. 21 . In  FIG. 22 , the sheet of film material  67  is heated by heating element  63  as frame  64  engages or is positioned closely to the heating element  63 . Arrows  69  indicate that frame  64  is lowered after heating element  63  heats sheet of film material  67  ( FIG. 22 ). Male mold  70  is placed upon matrix  66  so that when the heated and softened sheet of film material  67  is lowered with frame  64 , the sheet of film material  67  deforms and conforms to the male mold  70  as shown in  FIGS. 23 and 24 .  
         [0090]     A vacuum is drawn through the matrix of opening  66  using the vacuum pump in base  61  as indicated by the arrows  71  in  FIG. 23 . When the vacuum is discontinued, the male mold  70  is withdrawn, and the female mold  15 A is formed as part of sheet  67  as shown in  FIGS. 24 and 25 . The female mold  15 A can then be removed using knife  72 .  FIG. 26  shows the completed female mold  15 A.  
         [0091]     It should be understood that the female mold  15 A can be used in place of the female mold  15  in the embodiment of  FIGS. 1-19  and in the method of  FIGS. 1-19 .  
         [0092]      FIGS. 27-32  show a second alternate embodiment of the apparatus of the present invention, and illustrate the second alternate embodiment of the method of the present invention. In  FIGS. 27-32 , a second, alternate embodiment of the apparatus of the present invention is shown, designated generally by the numeral  75  in  FIGS. 29, 30  and  31 . Hearing aid  75  is constructed using the method shown in  FIGS. 27-32 . In  FIG. 27 , vent tube  76  is shown prior to attachment to mounting member (e.g. acrylic)  77 . The mounting member  77  has an opening  78 . It should be understood that the mounting member  77  can receive any of the female molds  15 ,  15 A shown in the embodiments of  FIGS. 1-26 .  
         [0093]     An insert  79  includes several sections designed to simulate portions of a hearing aid component assembly  105 . For example, the insert  79  can include a section  80  designed to simulate an electronic hearing aid component, namely a receiver. The insert section  81  is designed to simulate a wiring harness. The insert section  82  is designed to simulate a battery compartment or battery receptacle.  
         [0094]     Once the selected mold such as  15 ,  15 A is attached to mounting member  77 , it can be filled with a polymeric material (preferably silicone), such as is shown in  FIG. 11 . However, in the embodiment of  FIGS. 27-32 , vent tube  76  is first coated with a bonding agent  149  such as A330 available from Factor II of Lakeside, Ariz. The vent tube  76  is then placed inside the mold cavity  15 ,  15 A. The mold  15 ,  15 A is then attached (bonded) to mounting member  77  as shown and described with respect to the embodiments of  FIGS. 1-26  (see  FIG. 11 ). Once the polymeric material has cured inside mold cavity, the mold  15 ,  15 A can be removed as indicated schematically by arrow  94 . A technician then removes insert  78  as indicated schematically by the arrow  83  in  FIG. 28 . The insert  79  includes an insert section  80  that simulates a receiver, an insert section  81  that simulates a wiring harness and an insert section  82  that simulates a battery compartment or battery receptacle. However, other shapes can be used for insert  136  so that a cavity  141  of desired shape is achieved. Upon removal of the insert  79 , a cavity  84  is left behind, the cavity  84  being positioned next to vent tube  76  as shown in  FIG. 28 .  
         [0095]     The cavity  84  simulates the sections of the provided insert  79 , including a cavity section  85  that simulates a receiver, a cavity section  86  that simulates a wiring harness and a cavity section  87  that simulates a battery case or receptacle.  
         [0096]     The bonding enhancer  92  can be applied to vent tube  76  using a spray or brush  88  as shown in  FIG. 27  as indicated schematically by the arrow  89 . Vent tube  76  thus has an outer surface  90  that becomes coated with the bonding enhancer or bonding agent  92 . Vent tube  76  provides a bore  91  which is not coated with the bonding enhancer, as it remains open to vent air flow in between the patient&#39;s ear canal and the exterior of the ear canal and hearing aid  75 .  
         [0097]     The polymeric filler material  93  that is added to mold  15 ,  15 A cavity forms a soft and solid body having the provided cavity  84  into which a hearing aid component assembly  105  can be inserted, as indicated schematically by arrows  99  in  FIG. 29 . This hearing aid component assembly can include both electronic hearing aid components and other components. As an example, in  FIG. 29 , the hearing aid component assembly  105  includes a receiver  95 , receiver tube  96 , wiring harness  97 , and a battery compartment  98  that includes other hearing aid components such as battery  101 , a microphone, an amplifier, or other desired hearing aid components.  
         [0098]      FIGS. 29-31  illustrate the completion of and insertion of hearing aid component assembly  105  into the cavity  84  that was formed after the polymeric filler material  93  had cured and set, and after which the shaped insert  79  had been removed. In  FIG. 31 , arrows  100  schematically indicate a severing of excess vent tube  76  material and the severance of excess material from receiver tube  96 . The receiver tube  96  and vent tube  76  communicate with the patient&#39;s inner ear generally opposite mounting member  77  as shown in  FIGS. 28-31 . The vent tube  76  also communicates with the exterior of the patient&#39;s ear via an opening  104  in mounting member  77  (see  FIG. 32 ). A connection  103  can be formed between vent tube  76  and mounting member  77  using a needle  102  to apply an adhesive or other connection material or structure, for example.  
         [0099]     The apparatus  10  of the present invention will result in a better utilization of advanced circuitry and a more comfortable hearing instrument. The soft construction solves the problem of peripheral leakage, poor fit, and pivotal displacement that often occurs with jaw motion.  
         [0100]     Another problem that is solved with the present invention is the elimination of internal cross-talk of components housed in hollow shell type hearing aids.  
         [0101]     The following table lists the parts numbers and parts descriptions as used herein and in the drawings attached hereto.  
                                         PARTS LIST            Part Number   Description                1   ear        2   external auditory canal        3   ear canal wall        4   auricle        5   isthmus        6   tympanic membrane        7   middle ear        8   inner ear        9   dam       10   hearing aid       11   form       12   knife       13   excess material       14   excess material       15   female mold        15A   female mold       16   sagittal plane       17   vessel       18   technician&#39;s fingers       19   annular surface       20   arrow       21   mold material       22   mounting member       23   medial side       24   lateral side       25   microphone       26   battery compartment       27   volume control       28   programming socket       29   vent opening       30   vent tube       31   battery       32   battery terminal       33   voltage regulating capacitor       34   amplifier/microprocessor       35   receiver       36   receiver port       37   receiver tube       38   wiring harness       39   s-loop wires       40   arrow       41   opening       42   opening       43   opening       44   distal end       45   proximal end       46   dotted line       47   temporary seal       48   syringe       49   needle       50   filler material       51   arrow       52   arrow       53   interior space       54   silicone plug       55   monofilament cantilever       56   opening       57   fastener       58   small opening       59   large opening       60   vacuum mold       61   base       62   post       63   heating element       64   frame       65   opening       66   matrix       67   sheet of film material       68   arrow       69   arrow       70   male mold       71   arrow       72   knife       75   hearing aid       76   vent tube       77   mounting member       78   opening       79   insert       80   insert section       81   insert section       82   insert section       83   arrow       84   cavity       85   cavity section       86   cavity section       87   cavity section       88   brush       89   arrow       90   outer surface       91   bore       92   bonding agent       93   filler material       94   arrow       95   receiver       96   receiver tube       97   wiring harness       98   battery compartment       99   arrow       100    arrow       101    battery       102    needle       103    connection       104    opening       105    hearing aid component assembly                  
 
         [0102]     The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims.