U.S. patent number 3,602,330 [Application Number 05/041,812] was granted by the patent office on 1971-08-31 for acoustic ear mold for hearing aid.
Invention is credited to Rubein V. Johnson.
United States Patent |
3,602,330 |
Johnson |
August 31, 1971 |
ACOUSTIC EAR MOLD FOR HEARING AID
Abstract
An acoustic ear mold insertable into the ear of an individual
with impaired hearing and used in conjunction with a hearing aid
amplifier incorporates therein reflection chambers. Amplified sound
wave energy conducted to the ear mold proceeds to the hearing part
of the brain over two separate routes, one route being by way of
the tympanic membrane and the second route being by bone conduction
through the mastoid process.
Inventors: |
Johnson; Rubein V. (Muskogee,
OK) |
Family
ID: |
21918455 |
Appl.
No.: |
05/041,812 |
Filed: |
June 1, 1970 |
Current U.S.
Class: |
181/135;
381/326 |
Current CPC
Class: |
H04R
25/652 (20130101); H04R 2460/13 (20130101) |
Current International
Class: |
H04R
25/00 (20060101); G02k 013/00 (); H04r
025/00 () |
Field of
Search: |
;179/17BC,17E |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Tomsky; Stephen J.
Claims
What is claimed:
1. An improved hearing aid ear mold insertable into the external
auditory meatus of the ear and having a longitudinal canal for the
conduction of sound waves to the tympanic membrane of the ear; said
improvement comprising;
a first reflection chamber disposed in said ear mold transversally
to and communicating with said canal at opposed points; said first
reflection chamber having an upper closed end and an open lower
end;
a second reflection chamber received in the lower end of said first
reflection chamber and communicating therewith;
a bone contactor bar carried by said ear mold and abutting said
first and second reflection chambers and adapted for engagement
with the epidermis overlying the bony structure of the auditory
meatus whereby sound wave energy conducted through said canal is
reflected by said chambers into the mastoid bone process of the ear
through said bone contactor bar for bone conduction to the hearing
part of the brain.
2. An improved hearing aid ear mold as in claim 1 wherein said
first and second reflection chambers are cylindrical and said
second chamber is normal to said first chamber.
3. An improved hearing aid ear mold as in claim 1 wherein said
chambers and bar are made of gold.
Description
BACKGROUND OF THE INVENTION
This invention relates to hearing aids and more particularly to an
ear mold for a hearing aid.
Heretofore hearing aids have been developed for amplifying sound
waves and to conduct the amplified waves to the tympanic membrane
of the ear in order to improve the hearing of an individual.
Presently manufactured hearing aid apparatus includes an amplifier
and an ear mold which are insertable in the ear. Amplified sound
wave energy created by the amplifier is usually air conducted to
the ear mold wherein a longitudinal canal conveys the amplified
sound wave energy to the tympanic membrane of the ear where the
normal hearing process is commenced; that is, the sound wave energy
strikes the tympanic membrane, and then travels on to the malleus,
the incus, the stapes to the oval window and on through the fluid
of the sacs of the internal ear where the cochlea contains the
organ of the corti with associated nerve endings of the auditory
nerve from the brain.
A disadvantage of the presently manufactured ear molds is that
improved hearing is contingent solely upon sound wave
amplification. If for example otosclerosis has rendered immovable
or partially immovable the stapes due to ankylosis in the oval
window, the effectiveness of a hearing aid is lost. Also in many
instances where a high level amplification is necessary, sound
saturation results, whereby the normal process of hearing becomes
traumatized and the degree of hearing is not aided insofar as
intelligibility is concerned.
In addition to the normal air conduction process of hearing by way
of the tympanic membrane, sound wave energy can also be conducted
to the hearing part of the brain by means of bone conduction. In
bone conduction hearing, vibratory sound wave energy is transmitted
to the brain over a separate and distinct route from the normal
hearing process. Sound wave energy directly enters the mastoid
process and travels by bone conduction to the hearing part of the
brain for discrimination and interpretation. Thus bone conduction
hearing can be beneficial in reinforcing sound wave energy
transmitted to the brain by the normal air conduction process.
It is therefore an object of this invention to present an improved
acoustic ear mold for bone conduction of sound wave energy.
It is another object of this invention to present an improved ear
mold wherein amplified sound waves are conducted to the tympanic
membrane of the ear and simultaneously therewith to the bones of
the mastoid process such that sound wave energy is conveyed by two
separate routes to the hearing understanding part of the brain for
speech and sound discrimination, interpretation and
understanding.
SUMMARY OF THE INVENTION
Generally the improved acoustic ear mold of this invention contains
as an integral part thereof reflection chambers which divert and
convert air conduction sound waves into bone conduction sound waves
while yet allowing air conduction sound waves to pass to the
tympanic membrane for entrance into the normal hearing process. The
reflection chambers pass sound wave energy into the bones of the
mastoid process for conduction to the hearing part of the brain.
The bone conducted sound wave energy reinforces the air conducted
sound wave energy and increases the sound discrimination,
interpretation and understanding of the amplified sound waves
entering the ear mold.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of an ear mold for use in conjunction with an
amplifier of a hearing aid and incorporating the improvements of
this invention.
FIG. 2 is a cross-sectional view of the ear mold taken along lines
2--2 of FIG. 1.
FIG. 3 is a cross-sectional view of the ear mold of this invention
taken along lines 3--3 of FIG. 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now to the drawings, there is shown an ear mold
incorporating the improvements of this invention. The design of the
ear mold, generally noted as the numeral 10, is merely one of the
many types commercially available to the industry, and the exact
configuration thereof in no way limits the application of the
improvement of this invention. Ear mold 10, insertable over the
external auditory meatus portion of the ear, includes a
longitudinal canal 12 in which is received a pliant plastic tube 14
which conducts amplified sound waves from the amplifier of the
hearing aid (not shown). The amplifier of the hearing aid may be of
any of the various types commercially available. By way of example,
the amplifier may be contained in the template of a pair of glasses
or, in other instances, may be a solid state device carried by the
ear mold itself. Canal 12 conducts amplified sound waves received
from the amplifier through the ear mold and presents the same to
the tympanic membrane of the ear where the normal hearing process
is initiated.
Turning now to the specific improvement of this invention and to
the apparatus for improving the hearing ability of a person having
impaired hearing, snugly fitted in a hole transversal to the canal
12, at a slight oblique angle thereto, is a first reflection
chamber 16 composed of a cylindrical tube 18 capped on the upper
end by a reflection plate 20. Tube 18 may be fabricated from
various materials of various sizes, for example, such could be a
14-Kt. gold tube having a size 8 outer diameter. Chamber 16
communicates with canal 12 through opposed apertures 22 and 24 in
the wall of the tube 18. Due to the curvature of the canal 12,
aperture 24 is slightly vertically offset from aperture 22 and is
also of smaller diameter. Apertures 22 and 24 enable air sound wave
energy emanating from the amplifier of the hearing aid within
plastic tube 14 to pass into and exit from chamber 16.
Referring now to reflection plate 20, the upper end of tube 18 is
beveled outwardly to form a receiving service therefor. Reflection
plate 20 is retained on the upper end of tube 18 by means of gold
solder 26 which is sanded to conform to the shape of the ear mold
10, as can be seen in the drawings. Reflection plate 20 is
constructed of a hard metallic surface such as 18-Kt. gold and
includes a solid smooth undersurface perpendicular to the
longitudinal axis of tube 16 and which totally reflects sound wave
energy impinging thereon without any diffusion thereof. In other
words, the undersurface of reflection plate 20 serves as a sounding
board for sound wave energy, as will become evident in the
subsequent discussion.
Turning now to the lower end of tube 18, there is received therein
a second reflection chamber 28 having a longitudinal axis normal to
the axis of the chamber 16 and comprised of a circular cylinder. In
order to insure a tight fit of chamber 28 in the lower end of tube
18, tube 18 is routed to accept the ends of chamber 28. When
received within tube 18, chamber 28 is flush with the lower end
thereof and contains an upward transverse aperture 30 coaxial with
the longitudinal axis of chamber 18.
Embedded in mold 10 is a bone contactor bar 32 contiguous with the
lower end of chamber 16 and the outer wall of chamber 28. Bone
contactor bar 32 is also made of a metallic substance such as
18-Kt. gold and is shaped to conform to the curvature of the bony
structure of the auditory meatus and when the ear mold 10 is
inserted in the ear, the contactor bar is contingent with the skin
covering the bony structure so as to cause a transference of sound
wave energy from the bone contactor bar into the bony structure for
bone conduction of the energy to the brain.
In operation, amplified sound wave energy provided by the amplifier
of the hearing aid, enters the acoustic ear mold through the
plastic tube 14 and passes into the first reflection chamber 16
through aperture 22. The sound wave energy entering chamber 16
impinges upon the inner wall thereof, is reflected upwardly against
the reflection plate 20 and then is reflected downwardly without
diffusion to the second reflection chamber 28 through aperture 30.
Sound wave energy then passes into the contactor bar 32 and thence
into the bony structure of the auditory meatus for conduction to
the hearing part of the brain through the mastoid process.
Simultaneously with the bone conduction, sound wave energy also
exits from first reflection chamber 16 and is conducted through
canal 12 on to the tympanic membrane where the normal hearing
process is initiated.
Thus the acoustic ear mold of this invention provides for both
conduction of sound wave energy of the same intensity and frequency
to simultaneously travel over two separate routes to the hearing
understanding part of the brain; thereby enabling the person to
have a greater speech and sound discrimination, interpretation and
understanding of that which has been transmitted. As can be seen
from the aforementioned discussion, this bidirectional conduction
of sound waves to the hearing part of the brain enables a person to
improve his hearing and does not involve any moving physical
members.
While gold has been referred to herein as the metal of which
certain elements of the invention may be formed, it is understood
that this is by way of example only and that other metals may be
used with effectiveness.
During the detailed description of the preferred embodiment,
specific language has been used for the sake of clarity. However,
it is to be understood that the language used is for the sake of
clarity only, and are not words of limitation, but include all
equivalents which operate in a similar manner to accomplish similar
purposes.
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