Note: Descriptions are shown in the official language in which they were submitted.
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1
OTOPLASTIC
The present invention relates to an otoplasty with at
least one acoustic/electric transducer and/or at least
one electric/acoustic transducer, each with an acoustic
input/output, said input/output being connected via an
acoustic lead to a coupling opening on the outer face
of the otoplasty shell.
In otoplasties of the type mentioned, in particular in
hearing devices, either in-the-ear hearing devices or
hearing devices worn outside the ear, the acoustic
inputs to acoustic/electric input transducers,
microphones, and/or the acoustic outputs from
electric/acoustic output transducers, loudspeakers, are
usually connected via acoustic lead components, for
example in the form of small tubes, to coupling
openings on the outer face of the otoplasty shell,
unless these inputs/outputs are arranged directly in
the surface area of said shell. This approach is
disadvantageous from various aspects:
The geometric arrangement and orientation of the
coupling opening, on the outer face of the otoplasty
shell, to input transducers is principally determined
by desired acoustic reception characteristics. Thus,
the acoustic reception characteristics can be
determined by the distance and the position of such
coupling openings with respect to the otoplasty, a
hearing device. The position of a coupling opening on
the output side of an output transducer is also
determined, for example, by the relative position of
the otoplasty in the auditory canal and the ear drum.
In the case of a hearing device worn outside the ear,
in which a further tube-like acoustic lead for example
extends from the outer face of the otoplasty into the
auditory canal, said coupling opening has to be
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2
arranged in such a way that said additional acoustic
lead can be routed optimally along the auricle into the
auditory canal. If the position of this coupling
opening is set by parameters of the type mentioned,
then one or more transducers have to be integrated in
the otoplasty, depending on the available construction
space, and have to be connected to the coupling
openings via said acoustic leads. Taking into
consideration the fact that in active otoplasties of
this type, such as said hearing devices, the space
available for accommodating transducers and other
functional groups of the electronics, including the
battery, is extremely small, it is obviously often
quite difficult, with the desired position of the
coupling openings, to integrate the transducers and
acoustic leads into the otoplasty in a way which takes
optimal account of the available space and the acoustic
conditions.
The object of the present invention is to overcome
these disadvantages and to propose an otoplasty of the
type mentioned which permits great flexibility in the
constructional positioning of the transducers provided
in the otoplasty, largely independently of the position
of the coupling openings, and without having to give
too much consideration to the amount of space taken up
by separate acoustic connections to be provided. An
objective is to permit flexible incorporation of said
transducers at the best possible position from the
point of view of the most compact design, regardless of
the position of the coupling openings on the outer face
of the otoplasty shell, and without having to attach
too much importance to the acoustic connection lines or
the structural volume to be provided for these lines.
In said otoplasty, this is achieved by the fact that
the acoustic lead is bounded, as a channel, by the
material of the otoplasty shell.
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3
In other words, said acoustic lead is formed integrally
in the otoplasty or its shell. Since the otoplasty is
to be provided anyway with a shell with a given wall
thickness, the acoustic leads to be provided to the
coupling opening or openings take up only an
inconsequential structural volume in the otoplasty, and
the leads can be routed basically between any desired
positions. If appropriate, a plurality of acoustic
leads or channels can also be routed in parallel in
terms of signaling, at least in some areas. Thus, for
example, an area of the otoplasty where the space
needed for a channel of desired cross-sectional area is
not available can be circumvented by two or more
parallel signaling channels of smaller cross-sectional
areas: the first-mentioned channel branches off, and
the branch channels rejoin at the end of a given
course.
Therefore, the present invention concerns a hearing device comprising: a one-
part shell member forming at least a portion of an outer surface and of an
inner
surface towards an inner space of said device, said shell member forming a
channel out of the material of said shell member, said channel being formed in
and along said shell member embedded in said shell member over at least a
major portion of the length of said channel over said major portion following
a
contour of said outer surface; and at least one of an acoustical/electrical
converter and an electrical/acoustical converter including an acoustical input
or
output, respectively, wherein said input or output is acoustically linked to a
coupling opening via said channel forming an acoustic path from said input or
output to said coupling opening at an outer surface of said device and adapted
to be exposed to ambient or an ear canal of an individual wearing said hearing
device but not both, and further wherein said channel is tuned to have
specific
acoustical characteristics.
The present invention also concerns a hearing device comprising an
acoustical/electrical converter with an acoustical input being linked by means
of
CA 02422425 2008-09-15
3a
a channel to a coupling opening arrangement exclusively at an outer surface of
said device adapted to be exposed to ambient when an individual wears said
hearing device, said device having a unitary shell member forming said outer
surface and defining an inner space distinct from said channel, said channel
being a part of said shell member formed by and embedded in the material of
said shell member along a major portion of the length of said channel provided
in and along said shell member with the major portion of said length following
a
contour of said outer surface.
Furthermore, the present invention concerns a hearing device comprising: a
one-part shell member forming at least a portion of an outer surface and of an
inner surface towards an inner space of said device, said shell member forming
a channel out of the material of said shell member, said channel being formed
in
and along said shell member embedded in said shell member over at least a
major portion of the length of said channel, said major portion of said
channel
following a contour of said outer surface; an electrical/acoustical converter
including an acoustical output, wherein an acoustic path is formed from said
output to a coupling opening in said shell member and comprises said channel.
In a preferred embodiment, said at least one channel
has varying cross-sectional areas and or.varying cross-
sectional shapes from portion to portion along its
length, the aim being to optimize the acoustic
transmission behavior in a specific manner. In this
way, networks of acoustic impedances are created along
the channel, which permit optimum acoustic adaptation.
In a further embodiment, the impedance adaptation can
be realized by at least one adaptive stub line which
opens into the channel. In order to bridge greater
distances between said transducer and the coupling
opening on the otoplasty according to the invention, it
is proposed to route the at least one channel, at least
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3b
along a substantial portion of its length,
substantially parallel to the outer face of the
otoplasty.
Although the otoplasty according to the invention can
readily be conceived as a headphone part, the proposed
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4
procedure is particularly suitable for hearing devices.
If the hearing device is designed as an in-the-ear
hearing device, then it is further proposed that the
channel is part of a ventilation system for the
eardrum. This is made possible in particular by the
above-described possibilities of impedance adaptation.
The invention is explained below by way of example and
with reference to the figures, in which:
Fig. 1 shows a simplified diagram of a production
installation operating according to the
preferred method for optimizing the
industrial production of otoplasties;
Fig. 2 shows a further installation concept, in a
view analogous to that in Fig. 1;
Fig. 3 shows yet another installation concept in a
view analogous to that in Figures 1 and 2;
Fig. 4 shows a diagrammatic view of an in-the-ear
hearing device, with an earwax protection cap
fitted in a known manner;
Fig. 5 shows, in a view analogous to Fig. 4, an in-
the-ear hearing device produced with an
integral earwax protection cap;
Fig. 6 shows an in-the-ear hearing device with a
ventilation groove formed in it in a known
manner;
Figures 7 (a) through (f) show
perspective views of cutouts from otoplasty
shell surfaces with novel ventilation
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grooves;
Fig. 8 shows, based on a diagrammatic cutout of an
otoplasty surface, a ventilation groove with
5 a cross section and cross-sectional shape
varying along its longitudinal extent;
Fig. 9 shows a diagrammatic view of an in-the-ear
otoplasty with lengthened ventilation groove;
Fig. 10 shows, in a view analogous to Fig. 9, an in-
the-ear otoplasty with a plurality of
ventilation grooves;
Figures 11 (a) through (e) show
cutouts of otoplasty shells with ventilation
channels of different cross-sectional shapes
and dimensions formed in them;
Fig. 12 shows, in a view analogous to that in Fig. 8,
a ventilation channel in an otoplasty shell
with a cross-sectional shape and cross-
sectional surface varying along its
longitudinal extent;
Fig. 13 shows, diagrammatically in analogy to the
view in Fig. 9, an in-the-ear otoplasty with
a lengthened ventilation channel formed in
it;
Fig. 14 shows, in a view analogous to Fig. 10, an in-
the-ear otoplasty according to the invention
with a plurality of ventilation channels;
Fig. 15 shows a diagrammatic view, in longitudinal
section, of an in-the-ear otoplasty with
ribbed inner surface;
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Fig. 16 shows a cutout of the otoplasty according to
Fig. 15 in cross section, the ribs having
different cross-sectional surfaces;
Fig. 17 shows a perspective view of the cutout of an
otoplasty shell with inner ribbing according
to Fig. 15 or 16, the ribs having different
cross-sectional shapes and dimensions along
their longitudinal extent;
Fig. 18 shows, in a view analogous to Fig. 15, an in-
the-ear otoplasty with outer ribbing;
Fig. 19 shows a diagrammatic view of a cutout of a
ribbed otoplasty shell according to Fig. 18,
with ribs having different cross-sectional
surfaces;
Fig. 20 shows a diagrammatic view of a cross section
through an otoplasty with outer ribbing, or
inner ribbing, and an interior at least
partly filled with filler material;
Fig. 21 shows a diagrammatic cutout, in longitudinal
section, of an otoplasty shell with a part
which is flexible upon bending and
compression;
Fig. 22 shows a diagrammatic view, in longitudinal
section, of an in-the-ear otoplasty with a
receiving space for an electronic module;
Fig. 23 shows the otoplasty according to Fig. 22
being pushed on over an electronic module;
Fig. 24 shows a perspective and diagrammatic view of
an in-the-ear otoplasty, such as in
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particular an in-the-ear hearing device, with
a two-part, separable and connectable
otoplasty shell;
Fig. 25 shows, in a diagrammatic and cutaway view,
the integration, according to the invention,
of acoustic leads and adapter members to an
acoustic/electric or electric/acoustic
transducer, in an otoplasty;
Fig. 26 shows, in a view analogous to that in
Fig. 25, the arrangement, according to the
invention, of two or more acoustic leads in
the shell of an otoplasty shell, and
Fig. 27 shows, in a simplified signal flow chart and
functional block diagram, a novel procedure,
and a novel arrangement for carrying out the
procedure, where the dynamics of the
application area of an otoplasty are taken
into consideration when configuring the
latter.
The embodiments of otoplasties which are described
following the production method are preferably all
produced by this described production method.
Definition
An otoplasty is to be understood here as being a device
which is fitted directly outside the auricle and/or on
the auricle and/or in the auditory canal. These include
hearing devices worn outside the ear, in-the-ear
hearing devices, headphones, inserts protecting against
noise and inserts protecting against water, etc.
1. Production method
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In the production method preferably used to produce the
otoplasties described in detail hereinafter, the shape
of an individual application area for the intended
otoplasty is three-dimensionally digitized, and the
otoplasty or its shell is then constructed by an
additive construction method. Additive construction
methods are also known by the term "rapid prototyping".
With regard to additive methods which have already been
used in rapid prototyping, reference is made for
example to:
= Wohlers Report 2000, Rapid Prototyping
& Tooling State of the industry (1)
From the group of these additive methods known today
for rapid prototyping, it appears that laser sintering,
laser lithography or stereolithography, or the
thermojet method are particularly well suited for
constructing otoplasties or their shells, and in this
case in particular the specific embodiments described
hereinafter. Therefore, specifications of these
preferably used additive construction methods will be
discussed here, only in a brief summary:
= Laser sintering: hot-melt powder is applied in a
thin layer on a powder bed, for example by means
of a roller. The powder layer is solidified by
means of a laser beam, said laser beam being
guided, inter alia according to a cutting layer of
the otoplasty or otoplasty shell, by means of a
3-D shape information of the individual
application area. A solidified cutting layer of
the otoplasty or of its shell is obtained in the
otherwise loose powder. This layer is lowered from
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9
the powder plane, and a new layer of powder is
applied over it, and this layer of powder is in
turn solidified by laser according to a cutting
layer, etc.
= Laser lithography or stereolithography: A first
cutting layer of an otoplasty or of an otoplasty
shell is solidified by means of W laser on the
surface of liquid photopolymer. The solidified
layer is lowered and is again covered by liquid
polymer. By means of said W laser, the second
cutting layer of the otoplasty or of its shell is
solidified on the already-solidified layer. Once
again, the laser positioning is controlled inter
alia by means of the 3-D data or information from
the individual, previously recorded application
area.
Thermojet method: The contour formation in
accordance with a cutting layer of the otoplasty
or of the otoplasty shell is carri/ed out, in the
same way as in an ink-jet printer, by liquid
application inter alia according to the digitized
3-D shape information, in particular also the
individual application area. The deposited cutting
"picture" is then solidified. Once again,
according to the principle of the additive
construction methods, the otoplasty or its shell
is built up by depositing layer after layer.
As regards additive construction methods, and the
preferred ones mentioned above, reference may be made
to the following further publications:
= "Selective Laser Sintering (SLS) of Ceramics",
Muskesh Agarwala et al., presented at the
CA 02422425 2008-09-15
Solid Freeform Fabrication Symposium, Austin,
Texas, August 1999, (2)
and
Donald Klosterman et al., "Direct Fabrication of
Polymer Composite Structures with Curved LOM",
10 Solid Freeform Fabrication Symposium, University
of Texas at Austin, August 1999. (3)
In principle, therefore, in additive construction
methods, a thin layer of material is in each case
deposited on a surface, either over the whole surface
as in laser sintering or stereolithography, or, as in
the thermojet method, already in the contour of a cut
of the otoplasty or of its shell under construction.
The desired cut shape is then stabilized and
solidified.
Once a layer has been solidified, a new layer is
deposited over this, as has been described, and this
new layer is in turn solidified and connected to the
already solidified layer lying below it. The otoplasty
or its shell is thus constructed layer by layer by
additive layer-by-layer application.
For industrial production, it is preferable not just
for the cutting layer of one individual otoplasty or
CA 02422425 2003-05-02
1_ :L
otoplasty shell to be deposited and solidified in each
case, but for a plurality to be deposited and
solidified simultaneously per individual. In laser
sintering, for example, the one laser, normally under
mirror control, successively solidifies the cutting
layers of a plurality of otoplasties or theii: shells,
before all the solidified cutting layers are lowered i'n
unison. Then, after a new layer of powder has been
deposited over all the already solidified and lowered
cutting layers, the plurality of further cutting layers
are forrned in turn. Des ;+ite this ~ parallel production,
the respective otoplasties or thei.x, shells are produced
individually by digital control..
In this case, in order to solidify the plurality of
cutting layers, either a single laser beam is used
and/or several beams are operated and controlled in
parallel.
In an alternative to this procedure, a cutting layer is
solidified in each case with orle laser, while at the same
time the layer of powder ir;w being depos.~.ted for the formation
of a further otoplasty or, ootoplasty shell. Thereafter, the
same laser will soilidify the prepared layer of powder
according to the cutta.ng =iayc:~r the further ot,oplast,y,
while the previously solir.:lifi.ed layer. is lowered and a new
layer of powder is dept::rs i. ted . `I'iie laser therl operates
intermittently between two or., rnore ot::opl.asties o:[: otoplasty
shells under construction, an.d. so the idle ti.me of the laser
occasioned by the depositi..on of powder for the formation of
one of the shells is expLoa.ted for solidification of a
cutting layer of another otoplasty under construction.
Fig. 1 shows, in a diagrammatic view, how, in one
embodiment, a plurality of otoplasties or their shells
are produced industrially in a parallel process by
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means of laser sintering or laser lithography or
stereolithography. The laser with control unit 5 and
beam 3 is mounted above the material bed 1 for powder
or liquid medium. At position 1, it solidifies the
layer S1 of a first otoplasty or its shell, controlled
by the first individual set of data Dl. Thereafter, it
is displaced on a displacement device 7 to a second
position where, with the individual set of data D2, it
prepares the layer S2 according to a further individual
contour. Of course, a plurality of the lasers can be
displaced as a unit and in each case two or more
individual otoplasty layers are prepared simultaneously.
It is only when the lasers 5 provided have prepared the
respective individual layers at all the intended
positions that a new layer of powder is deposited, in the
case of laser sintering, by the powder delivery means
represented in general at 9, whereas in laser
lithography and stereolithography (not shown) the
solidified layers S are lowered in the liquid bed.
According to Fig. 2, layers of individual otoplasties
or their shells are solidified simultaneously on one or
more liquid or powder beds 1 by a plurality of lasers 5
which are controlled individually and simultaneously.
Once again, after this solidification phase has been
completed and after the lasers have been stopped, the
powder delivery unit 9 deposits a new layer of powder,
while, in the case of laser lithography or
stereolithography, the layers which have just
solidified, or already solidified structures, are
lowered in the liquid bed.
According to Fig. 3, the laser 5 solidifies the layer
S1 on a powder or liquid bed la and is then transferred
(broken line) to the bed lb, so that, during the
solidification phase at the bed la, the powder
application device 9b removes powder from above a
previously solidified layer S1- or, in laser lithography
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13
or stereolithography, the layer S1- is lowered. It is
only when the laser 5 is active at the bed lb that the
powder delivery device 9a deposits a new layer of
powder over the layer S1 which has just solidified at
the bed la, or the layer S1 is lowered in the liquid
bed la.
When using the thermojet method, and to similarly
increase productivity, cutting layers of more than one
otoplasty or their shells are deposited simultaneously,
in practice through one application head or, in
parallel, through several in one go.
By means of the method described, it is possible to
obtain extremely complex shapes of otoplasties or their
shells, specifically as regards both their outer shape,
with individual adaptation to the application area, and
also, in the case of a shell, as regards their inner
shape. Overhangs and inward and outward protrusions can
be readily achieved.
Moreover, materials for additive construction methods
are known which can be shaped to give a rubber-elastic
and yet dimensionally stable shell, which, if so
desired, can be given local differences and even an
extremely thin wall and yet remain resistant to
tearing.
In a presently preferred embodiment, the digitization
of the individual application area, in particular the
application area for a hearing device, in particular an
in-the-ear hearing device, is undertaken in a
specialized institute, in the latter case by an
audiologist. The individual shape recorded there as
digital 3-D information is, particularly in connection
with hearing devices, sent to a production center,
either by transfer of a data carrier or via an Internet
link, etc. The otoplasty or its shell, in the present
case the shell of the in-the-ear hearing device, is
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14
shaped individually at the production center, in
particular using the abovementioned methods. The
fitting of the hearing device with the functional
component groups is preferably also carried out there.
On account of the fact that, as has been mentioned, the
thermoplastic materials used generally lead to a
relatively elastic, conformable outer shape, the
shaping with respect to pressure points in otoplasties
or their shells is also much less critical than was
hitherto the case, which is of huge importance in
particular for in-the-ear otoplasties. Thus, in-the-ear
otoplasties, for example as ear protectors, headphones,
devices protecting against water, but in particular
also for in-the-ear hearing devices, can be used
similarly to rubber-elastic plugs, and their surface
conforms optimally to the application area, i.e. the
auditory canal. One or more ventilation channels can be
easily incorporated in the in-the-ear otoplasty so
that, with the resulting and possibly relatively tight
fit of the otoplasty in the auditory canal, it is
possible to guarantee unimpaired ventilation as far as
the eardrum. The individual 3-D data from the
application area can also be used during production to
optimize the interior of the otoplasty and utilize this
optimally, including individually with respect to the
individual array of components which this interior is
possibly intended to receive, as in the case of a
hearing device.
Particularly in the case of otoplasties in the form of
hearing devices, centralized production of their shells
permits central storing and administration of
individual data, both with respect to the individual
application area and also to the individual functional
parts and their settings. If, for whatever reasons, a
shell has to be replaced, it can be newly prepared
without any problem by calling up the individual sets
CA 02422425 2003-03-05
of data, without the need for laborious readaptation,
as has hitherto been the case.
On account of the fact that the methods described for
5 the production of otoplasties are known and described
in the literature, albeit only for prototyping, it is
not necessary at this point to reproduce all the
technical details of these methods.
10 At any rate, taking these technologies previously known
from prototyping and using them for industrial and
commercially feasible production of otoplasties
surprisingly affords very considerable advantages,
specifically for reasons which in themselves are not
15 critical in prototyping, for example the elasticity of
the thermoplastic materials which can be used, the
possibility of individual construction with extremely
thin walls, etc.
In summary, by using said additive construction methods
for the production of otoplasties or their shells, it
is possible to integrate various functional elements on
them, which functional elements are constructively
prepared on computer during the planning of the
otoplasty and which are generated with the construction
of the otoplasty or its shell. Hitherto, functional
elements of this kind were typically fitted into or
onto the otoplasty or its shell only after the latter
had been produced, which is recognizable from material
interfaces or from lack of homogeneity of the material
at the connection points.
For said otoplasties, in particular those with
electronic inserts, for example for hearing devices,
and in particular for in-the-ear hearing devices,
examples of elements which can be fitted directly into
the otoplasty shell by the proposed technique are:
seats and holders for structural parts, earwax
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16
protection systems, ventilation channels in the case of
in-the-ear otoplasties, and support elements which hold
the in-the-ear otoplasty in the auditory canal, for
example channel locks.
Fig. 4 shows, in diagrammatic form, an example of an
in-the-ear otoplasty 11, for example an in-the-ear
hearing device in which the acoustic outlet 13 to the
eardrum is protected by means of an earwax protection
cap 15. This protection cap 15 has hitherto been
produced as a separate part and attached to the shell
16 of the otoplasty 11 and fixed, for example, by
adhesion or welding. As Fig. 5 shows in the same view,
by using said additive construction methods, the earwax
protection cap 15a is integrated directly on the shell
16a of the otherwise identical in-the-ear otoplasty
11a. At the connection points indicated schematically
by P in Fig. 4, where in conventional methods there is
necessarily a lack of homogeneity of the material or a
material interface, there are no such interfaces
according to Fig. 5, and the materiai of the shell 16a
merges homogeneously into that of the earwax protection
cap 15a.
This is just an example of how known earwax protection
systems and other functional elements can be integrally
incorporated by using said production method.
A number of specific, novel otoplasties are presented
below:
2. In-the-ear otoplasties with ventilation
In the case of in-the-ear otoplasties, in particular
in-the-ear hearing devices, it is known to provide a
ventilation groove on the outside, as is shown
diagrammatically in Fig. 6. Such ventilation grooves,
as they are used today, are not by any means optimal,
CA 02422425 2003-03-05
17
and for different reasons:
- As regards acoustics: The ventilation grooves
known today are not really adapted to the
particular acoustic requirements. Thus, in active
otoplasties, for example in-the-ear hearing
devices, they can do little to help effectively
solve the problems of feedback from electro-
mechanical output transducer to acoustic/electric
input transducer. In the case of passive in-the-
ear otoplasties too, for example ear protectors,
they are not able to support the desired
protective action and simultaneously maintain the
desired ventilation properties.
- Earwax sensitivity: The ventilation grooves used
today in the outer surfaces of in-the-ear
otoplasties are extremely sensitive to formation
of earwax. Depending on its intensity, this can
quickly impair the ventilation properties of the
ventilation grooves provided, if not completely
obstruct them.
Ventilation measures are proposed below for in-the-ear
otoplasties, in particular for in-the-ear hearing
devices or ear protectors, but also for otoplasties
which extend only partially into the auditory canal,
for example headphones, these ventilation measures at
least partly avoiding the abovementioned disadvantages
of known measures.
In this connection, a distinction is made below between
ventilation systems which
- are groove-like and at least partially open toward
the wall of the auditory canal,
- are completely closed off from the wall of the
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18
auditory canal.
2a) Ventilation systems open toward the wall of the
auditory canal
in Figures 7(a) through (f), which are perspective
diagrammatic views of cutouts of the outer wall 18 of
in-the-ear otoplasties which bears against the auditory
canal, novel ventilation groove profiles are shown in
cutaway view. According to Fig. 7(a), the profile of
the ventilation groove 20a is rectangular or square
with predetermined and exactly observed dimensional
relationships. According to Fig. 7(b), the profile of
the ventilation groove 20b is in the shape of a sector
of a circle or ellipse, again with an exactly
predetermined cross-sectional edge curve 21b. By exact
determination and execution of the cross-sectional
shape of the ventilation grooves 20 provided, it is
already possible to a certain extent to predict and
influence the acoustic transmission conditions along
this groove, upon bearing against the inner wall of the
auditory canal. Of course, the acoustic behavior also
depends on the length by which the groove 20 extends
along the outer wall 18 of the otoplasty.
Figures 7(c) through (f) show further ventilation
groove profiles which are additionally protected
against earwax. The profile of the groove 20c according
to Fig. 7(c) is T-shaped.
Regarding the wide cross-sectional surface of the
groove at 27c, the inwardly jutting portions 23c and
the resulting constriction 25c, toward the wall of the
auditory canal, already give a considerable protective
action against earwax. Even if earwax penetrates into
the constriction 25c and hardens there, this does not
cause any real constriction or even blockage of the
ventilation groove, which now becomes an enclosed
CA 02422425 2003-03-05
19
ventilation channel. In Figures 7(d) through 7(f),
which follow the principle of Fig. 7(c) already
explained, the cross-sectional shape of the wide groove
portion 27d through 27f is designed with different
shapes: in Fig. 7(d) in the shape of a sector of a
circle or the sector of an ellipse, in Fig. 7(e) in the
shape of a triangle, and in Fig. 7(f) in the shape of a
circle or ellipse.
By specific configuration of the cross-sectional
surface of the groove, shown simply by way of example
in Figures 7(a) through 7(f), it is already possible to
achieve a considerably improved effect, both with
respect to the acoustic properties and also with
respect to the protection against earwax, compared to
conventional ventilation grooves which have more or
less random profiles. In this case, the profiles are
first computer-modeled, taking into consideration said
protection against earwax and the acoustic effect, and
are integrated exactly into the finished otoplasties.
The additive construction methods discussed above are
very particularly suitable in this respect. In order
now to further optimize the acoustic effect of the
ventilation groove, a very wide variety of acoustic
impedances can be obtained along the length of the
novel ventilation grooves, which results, for example
as in Fig. 8, in ventilation grooves 29 defining
different profiles along their longitudinal extent,
which in Fig. 8 are optionally made up of profiles
according to Fig. 7.
Like the configuring of passive electrical networks,
the acoustic transmission behavior of the groove which
bears on the auditory canal can thus be computer-
modeled and checked and then integrated into the in-
the-ear otoplasty or its shell.
More areas protected against earwax can be specifically
CA 02422425 2003-03-05
provided on exposed portions for this purpose, as is
indicated at A in Fig. 8.
Moreover, with a view to optimizing the acoustic
5 conditions, it may be entirely desirable for the
provided ventilation grooves to be made longer than is
permitted in principle by the longitudinal extent of a
given in-the-ear otoplasty. As is shown in Fig. 9, this
is achieved by the fact that such grooves 31, designed
10 in the manner shown.for example in Figures 7 and 8, are
guided in predetermined curves along the surface of the
otoplasty, for example as is shown in Fig. 9, in
practice as grooves running round the otoplasty like a
thread. Further optimization flexibility is achieved by
15 the fact that not just one ventilation groove, but a
plurality are guided across the surface of the
otoplasty, as is shown diagrammatically in Fig. 10. The
high degree of flexibility of the groove design means
that, depending on the application area in the auditory
20 canal, differently dimensioned ventilation grooves
specifically optimized in each case with respect to
earwax protection and acoustic transmission behavior
can be formed along the surface of the otoplasty.
2b) Ventilation systems with fully integrated channels
This alternative embodiment of the novel ventilation
systems is based on ventilation channels which are
fully integrated into the otoplasty, at least in some
areas, and closed off from the wall of the auditory
canal. This system is explained below on the basis of
its design on an otoplasty shell. It should be
stressed, however, that when no other units are to be
integrated on the otoplasty in question and the latter
is designed as a solid otoplasty, the following
explanations naturally relate also to a channel passage
in any form right through said solid otoplasty.
CA 02422425 2003-03-05
21
Fig. 11 shows, in analogy to Fig. 7, different cross-
sectional shapes and surface relationships of the
proposed ventilation channels 33a through 33e.
According to Fig. 11(a), the {ventilation channel 33a
built into the otoplasty shell 35a has a rectangular or
square cross-sectional shape. In the embodiment
according to Fig. 11(b), it has, at 35b, a channel
cross-sectional shape in the form of a sector of a
circle or sector of an ellipse. In the embodiment
according to Fig. 11(c), the ventilation channel 33c
provided has a circular or elliptic cross section, and,
in the embodiment according to Fig. 11(d), it has a
triangular cross-sectional shape.
In the embodiment according to Fig. 11(e), the
otoplasty shell has a complex inner shape, for example
a retention part 37 integrated thereon. For optimal
utilization of space, the ventilation channel 35e
provided here is designed with a cross-sectional shape
which also makes use of complex shapes of the otoplasty
shell. Accordingly, its cross-sectional shape extends
in a complicated manner partially into the retention
strip 37 built onto the shell 35e.
Looking back at the variant embodiment in accordance
with section 2a), it should be noted that these complex
cross-sectional shapes optimally utilizing the
available space can also be realized on ventilation
grooves which are open toward the auditory canal, and,
conversely, channel passages as shown for open grooves
in Figures 9 and 10 can be realized on closed
ventilation channels.
Fig. 12 shows, finally, an alternative embodiment of a
fully integrated ventilation channel 39 which has
different cross-sectional shapes and/or cross-sectional
dimensions along its longitudinal extent, as is
represented for example in the otoplasty shell 41, in
CA 02422425 2003-05-02
-, ,.,
~.
~:.
which case the acoustic transmission hehavi.o.r can be optimized
in the sense of execut:i.rig d.iff:ex:-ent aco(isfi.i.c impedance elements.
In this connectiori, and with r e.f.er.ence tc) 3ubsequent section 5,
described later on in this application, it may also be
noted that, because of the possa..bi.lity of realizing
complex acoustic impedar.ice conditions, ventilation
channels, in particular of the c:l.osed configuration
presented in this sectiori, can at the same time be
used,, at least in some sections, as acoustic lead
sections on the output side of acti.ve electromechanical
transducers, for example on the output side of
microphones, for example in .i.n-the-ear hearing dev:i.ces.
Figures 13 and 14, in analogy to Figures 9 and 10,
show, on the one hand, how the integrated ventilation
channels discussed in this section are lengt:hened on
the respective otoplasty 43 by appropriate guiding of
their course, and, on the other hand, }-iow two and. more
of said channels, if appropriate with different and/or
varying channel. cross sections, in analogy to Fig. 12,
are integrated on the otoplast.y.
The possibilitiLes which are presented in sections 2a)
and 2b) , and which can also be combined in any desired
manner, afford the skilled person a countless number of
design variants of the novel ventilation systems and in
particular, because of the different independently
dimensionable parameters, a large d(:.~gree of freedom in
creating optimum earwax protection and optimum acoustic
transmission conditions for the re,spective individual
otoplasty. In all the embodiment vari.ants, the specific
individual configuration of the system is prefera:bly
calculated or computer-modeled, ;.aki..ng the stated
requirements into account. The indi'~ridual otoplasty is
then made. Once again, the production method with the
additive construction principle, which is knowri from
prototyping and which is explained ir:L the introduction,
is suitable for in particular this purpose, which
method is then controlled with the optimized model
CA 02422425 2003-03-05
23
result.
3. Otoplasties with optimized shape stability
This section deals with providing novel otoplasties
which are optimally adapted to the dynamics of the
application areas. It is known, for example, that
conventional in-the-ear otoplasties are unable to
accommodate the relatively great dynamics of the
auditory canal, for example during chewing, because
their shape stability is substantially identical in all
parts. Similarly, for example, the acoustic leads
between hearing devices worn outside the ear, and the
auditory canal are unable to freely follow the dynamics
of the application area. The same problem arises with
in-the-ear otoplasties, to a slightly lesser extent,
and also with ear protectors, headphones, inserts
protecting against water, etc. In particular, their
intrinsic function, for example their protective
action, in this case partially deteriorates if the
stated dynamics of the application area are
increasingly taken into consideration. By way of
example, reference may be made in this connection to
known ear protectors which are made of elastically
deformable plastics and which indeed take considerable
account of the stated dynamics of the application area,
but at the expense of their acoustic transmission
behavior.
Fig. 15 shows a diagrammatic view of a longitudinal
section of an in-the-ear otoplasty, and Fig. 16 shows a
diagrammatic cross-sectional view of a portion of this
otoplasty. The otoplasty, for example for receiving
electronic components, has a shell 45 which is made,
like a stocking, as a thin wall of elastic material.
The shape stability of the shell skin, which is smooth
on the outside in the illustrative embodiment shown, is
ensured, where so desired, by ribs 47 which are applied
CA 02422425 2003-03-05
24
integrally on the inside of the shell and which are
made of the same material as the shell skin.
Depending on the required dynamics of the in-the-ear
otoplasty on the one hand, in order for example to take
account of the dynamics of the auditory canal, and the
requirements in respect of the support and protection
of built-in components, as in an in-the-ear hearing
device, the course of the wall thickness of shell skin
45 and the density and configuration of the ribs 47 are
calculated in advance, and the otoplasty is thereafter
constructed according to the calculated data. Once
again, the above-discussed production method using
additive construction methods is outstandingly suitable
for this purpose. Of course, the design of the in-the-
ear otoplasty just discussed can be readily combined
with a ventilation system of the kind discussed with
reference to Figures 7 through 14. In particular, the
ribs provided to influence the shape stability or
bendability can also be designed with different cross-
sectional profile in certain areas of the otoplasty, if
appropriate also advancing from one cross section to
the other in their longitudinal extent.
In the form of a perspective view, Fig. 17 shows purely
by way of example and diagrammatically the design of
the outer skin 45 with ribs 47 having varying cross-
sectional surfaces along their longitudinal extent.
Instead of or in addition to the specific wall
strengthening and the specific configuration of the
bending and torsion behavior, in short of the shaping
behavior of the in-the-ear otoplasty, it is possible,
as has been mentioned, in addition to the internal
ribbing pattern as is shown in Figures 17 and 18, also
to provide an external ribbing pattern. According to
Figures 18 and 19, a pattern of ribs 51 is worked on
the outer surface of the otoplasty 49, if appropriate
with different density, orientation and profile shape
CA 02422425 2003-03-05
in different areas.
According to Fig. 19, this can be used for the
otoplasties in question here which have a hollow
5 cavity, but also for otoplasties with no hollow cavity,
that is to say, for example, with no electronic
components, e.g. for ear protector devices and devices
protecting against water. One such otoplasty is shown
diagrammatically in a cross-sectional view in Fig. 20.
10 Here, the interior 53 is made, for example, from
extremely compressible absorption material and is
surrounded by a shape-giving skin shell 55 with rib
pattern 57. Here, the "skin" 55 and the rib pattern 57
are integrally produced together. The production method
15 discussed in the introduction and using additive
construction methods is once again suitable for this
purpose. How far these additive construction methods
will be able to be used, in the near future, on a
workpiece with changing of the processed materials
20 remains to be seen. Should this become possible, then
the way is clear, for example in the illustrative
embodiment according to Fig. 20, to sequentially also
construct the filler 53 at the same time as the shell
skin 55 and the ribs 57 in respective construction
25 layers.
Looking back in particular to Figures 18 and 19, it
will be seen that ventilation channels or free spaces
can at the same time be formed with the aid of the
external ribbing pattern, as is shown purely
schematically and by way of example by the path P.
Returning once more to Fig. 20, it is entirely
possible, if so required, and as is shown by broken
line 57i in Fig. 20, to provide an internal ribbing
pattern 57;, on the shell skin 55 even if the in-the-ear
otoplasty is filled with material, that is to say if it
is not intended to receive further components, such as
CA 02422425 2003-03-05
26
electronic components. As is also shown by the broken
line 59 in Fig. 20, otoplasties can also be created
which indeed leave free a hollow cavity to receive
units such as electronic components, but in which the
interspace, between such a hollow cavity 59, is
designed specifically to the necessary volumes and
shapes of the units additionally to be received, and
the shell skin 55 is filled for example with a
resilient or sound-damping material, or components to
be incorporated are surrounded by such a material as
far as the shell skin 55.
The shell skin 55 or 45 according to Figures 15, 16 and
17 can be made entirely of electrically conductive
material, by which means an electrical screening effect
is at the same time created for electronic components
lying on the inside. This also applies, if appropriate,
to the filling 53 according to Fig. 20.
Figures 15 through 20 have shown an example of an
otoplasty in the form of an in-the-ear otoplasty whose
shell is shape-stabilized with ribs lying on the inside
and/or outside, resulting in an extraordinarily light
and deliberately formable structure. If necessary, this
structure can of course also be used for otoplasties
worn outside the ear.
Fig. 21 shows a further alternative embodiment of an
in-the-ear otoplasty which is deliberately bendable or
compressible in one area. For this purpose, the shell
61 of an otoplasty, such as in particular the shell of
an in-the-ear hearing device, has an undulated or
creased configuration 63 at one or more predetermined
regions where, in accordance with the particular
requirements, it is bendable or compressible. Although
Fig. 21 shows this measure on the basis of the shell of
an in-the-ear otoplasty, it is entirely possible, if
necessary, to provide this measure also for an
CA 02422425 2003-03-05
27
otoplasty worn outside the ear. For this purpose, the
production method discussed in the introduction is once
again preferably used.
In this illustrative embodiment too, it is possible, as
was explained with reference to Fig. 20, for the
internal volume of the otoplasty to be filled with
filler material in accordance with the requirements,
and built-in components integrated therein can be
embedded in such filler material, resulting in a higher
degree of stability of the appliance and improved
acoustic conditions.
4. Modular housing/built-in components
Particularly in the case of in-the-ear hearing devices,
the problem is that the application area, i.e. the
auditory canal, changes its shape. This is obviously
the case when a person is growing up. In adults too,
however, the auditory canal changes, sometimes
considerably, and in most cases in the sense of
narrowing (e.g. what is called diver's ear).
In the case of in-the-ear hearing devices, the problem
thus generally arises that, even if the components
built into the hearing device could themselves be
maintained over long periods of the user's life, for
example with only the transmission behavior of the
hearing device having to be readjusted to the
particular hearing conditions, new hearing devices
nevertheless have to be constantly designed, simply
because of the fact that the previous ones no longer
fit satisfactorily into the auditory canal.
The measures discussed in section 3 already make it
possible to improve this, on account of the fact that
automatic shape adjustment of the otoplasty to the
changing application areas is thus permitted. In this
CA 02422425 2003-03-05
28
section, further measures in this connection will be
discussed, particularly with reference to in-the-ear
otoplasties. However, it should be noted that also in
the case of otoplasties worn outside the ear, for
example hearing devices worn outside the ear, this
opens up the possibility of changing the "housing", and
of doing so not only when this is necessary for reasons
of wearing comfort, but also as and when desired, for
example in order to change the esthetic appearance of
such hearing devices worn outside the ear.
Fig. 22 shows a diagrammatic view of an in-the-ear
otoplasty 65 in longitudinal section, the design of the
interior 67 corresponding substantially to the shape of
the electronic module 69 to be received, which is shown
diagrammatically in Fig. 23. The otoplasty 65 is made
of rubber-elastic material and, as is shown in Fig. 23,
can be pushed on over the electronic module 69. The
shaping of the interior 67 is such that the module or,
if desired, the plurality of modules to be received are
positioned and held directly with a form fit by the
otoplasty 65. By means of this measure, it is easily
possible to provide one and the same electronic modules
69 with different otoplasties 65, for example in order
thereby to take account of the changing shape of the
auditory canal in a growing child. The otoplasty in
practice becomes an easily exchangeable throw-way
accessory for the in-the-ear hearing device. The
otoplasty 65 can be easily changed not only to take
account of changing conditions in the application area,
namely the auditory canal, but also simply for reasons
of soiling. This concept can even be used, if
appropriate, for example in cases of inflammation of
the auditory canal, to apply medicines, for example by
application of medicines to the outer surface of the
otoplasty, or at least in order to use sterilized
otoplasties at regular intervals.
CA 02422425 2003-03-05
29
The concept shown with reference to Figures 22 and 23
can of course be combined with the concepts set out in
sections 2 and 3, and the otoplasty 65 is preferably
produced using the production method discussed in
section 1), which permits the design of highly complex
internal shapes for receiving the module 69 in a manner
free from play and vibration.
As can be seen from Figures 22 and 23, the phase plate
1 otherwise provided in conventional in-the-ear hearing
devices is built integrally with the otoplasty, for
example as part of the module holder. The same applies
to other holders and receiving seats for electronic
components of the hearing device. If the layer-by-layer
construction method set out in section 1) is carried
out, as is indicated by broken lines in Fig. 22 and in
the direction shown by the arrow AB, then it ought to
be easily possible to produce the otoplasty from
different materials in said construction direction AB,
according to the requirements in the respective areas.
This applies also to the otoplasties set out in
sections 2) and 3), and to those discussed in sections
5), 6) and 7) below. Taking the example in Fig. 22, it
is thus quite possible to produce the area 65a using
rubber-elastic material, and by contrast the outlet
area 65b using more shape-stable material.
Fig. 24 shows a further embodiment of an otoplasty,
again taking the example of an in-the-ear hearing
device, which allows the internal built-in components
to be easily and quickly changed. In principle it is
proposed here that the otoplasty shell of an in-the-ear
otoplasty with built-in components is designed in a
plurality of parts which can be fitted together, as is
shown in Fig. 24. By means of quick-acting couplings,
such as snap-in couplings, catches or even bayonet-like
couplings, it is possible for housing parts 73a and 73b
of the in-the-ear otoplasty to be quickly separated
CA 02422425 2003-03-05
from one another, for the built-in components such as
electronic modules to be removed, and for these to be
inserted again into a new shell, if appropriate with
different outer shape, or in principle into a new shell
5 even when this is necessary, for example, for cleaning
reasons, sterility reasons, etc. If provision is made
for the already used shell to be disposed of, it is
easily possible to design the connections of the shell
parts in such a way that the shell can only be opened
10 by destroying it, for example by providing locking
members, such as catches, which are not accessible from
the outside and by the shell being cut open in order to
remove them.
15 This embodiment can of course also be combined with the
alternative embodiments described above and those still
to be described.
5. Integration of acoustic leads in otoplasties and
20 their shells
In hearing devices worn outside the ear, and also in
in-the-ear hearing devices, it is customary for the
provided acoustic/electric transducers or electro-
25 acoustic output transducers to be coupled, on the input
side or output side, to the environment of the hearing
device via acoustic leads assembled as independent
parts, namely tube-like structures, or, in particular
with acoustic/electric transducers on the input side,
30 to place these with their receiving surface immediately
in the area of the surfaces of the hearing device, if
appropriate separated from the environment only by
small hollow spaces and protective measures.
In the design of such hearing devices, there is
therefore a relatively large join where the actual
transducers are to be provided in the hearing device
and where the actual coupling openings to the
CA 02422425 2003-03-05
31
environment are to be provided on said hearing device.
As regards the arrangement of coupling openings to the
environment and the arrangement of said transducers
inside the hearing device, it would be highly desirable
to have the greatest possible design freedom.
This is in principle achieved by the fact that said
acoustic leads - at the input side of acoustic/electric
transducers or output side of electric/acoustic
transducers - are integrated into the otoplasty or into
the wall of otoplasty shells.
This is shown purely schematically in Fig. 25. A
transducer module 75 has an acoustic input/output 77.
The shell 79 of the otoplasty of an in-the-ear hearing
device, or of a hearing device worn outside the ear, or
of headphones, has an acoustic lead 81 integrated
within it. This lies at least partially within the wall
of the otoplasty shell 79, as is shown in Fig. 25. The
respective acoustic impedance of the acoustic lead 81
is preferably adapted by means of acoustic stub lines
or line sections 83. This concept, taking the example
of hearing devices worn outside the ear, makes it
possible to provide acoustic input openings 85
staggered along the hearing device and at desired
locations, and to couple said inlet openings 85 to the
provided acoustic/electric transducers 91 via acoustic
leads 89 integrated in the otoplasty or its shell 87,
and largely irrespective of where these transducers 91
are built into the hearing device. Thus, Fig. 26 shows,
only by way of example, how two transducers are
centralized into one module and their inputs are
connected to the desired receiving openings 85 via said
path of the acoustic leads 89. In the light of Figures
25 and 26 and the statements in section 2) regarding
the novel ventilation systems, it will be evident that
it is quite possible to use ventilation channels also
as acoustic lead channels, especially if, as is shown
CA 02422425 2003-03-05
32
diagrammatically in Fig. 25, the acoustic impedance
conditions are specifically configured by means of
acoustic adapter members 83.
6. Identification of otoplasties
In the production of otoplasties, in particular of in-
the-ear otoplasties, each one is individually adapted
to its respective wearer. For this reason, it would be
highly desirable to identify each finished otoplasty,
as mentioned in particular each in-the-ear otoplasty,
and very particularly each in-the-ear hearing device.
It is therefore proposed to provide an individual
identification in the otoplasty or its shell by means
of indentations and/or embossings, which
identification, in addition to giving the individual
orderer, for example manufacturer, can contain the
product serial number, left/right application, etc.
Such an identification is created in a much preferred
manner during the production of the otoplasty using the
removal method described under 1) . This ensures that
any mix-up of the otoplasties is ruled out starting
from the time of production. This is particularly
important in the subsequent and possibly automatic
fitting with further modules, for example the fitting
of in-the-ear hearing devices.
This measure can of course be combined with one or more
of the aspects described under sections 2) through 5).
7. Optimization of otoplasties with respect to the
dynamics of the application area
When molding otoplasties for in-the-ear application,
for example for in-the-ear hearing devices, it is at
present customary to take an impression of the auditory
canal, for example using silicone. If one now considers
the quite substantial dynamics of movement of the
CA 02422425 2003-03-05
33
auditory canal, for example during chewing, it is
evident that basing the shape of the in-the-ear
otoplasty on an impression, which corresponds in
practice to a momentary record, can scarcely yield a
result which will be entirely satisfactory in use. As
is now shown in Fig. 27, which is a simplified
functional block diagram/signal flow chart, a mold is
taken from the dynamic application area, represented by
the block 93, at several of the positions corresponding
to the dynamics occurring in practice, or the dynamics
of the application area are recorded per se in the
manner of a film. The resulting data sets are stored in
a memory unit 95. Also in the conventional procedure
with impression-taking, this can be readily done by
taking impressions, corresponding to the practical
dynamics, of the application area at two or more
positions.
These impressions are then scanned and the respective
digital data sets are stored in the memory unit 95. As
a further possibility, the dynamics of the application
area can be recorded by X-ray, for example.
Thus, depending on the accuracy which is to be
achieved, a number of "images" or even in practice a
"film" of the pattern of movement of the application
area in question are recorded. The data recorded in the
memory unit 95 are then fed to a computer unit 97. At
its output, the computer unit 97 controls the
production process 99 for the otoplasty. If, for
example, as is still customary today, in-the-ear
otoplasties are produced with a relatively hard shell,
the computer unit 97 uses the dynamics data stored in
the memory unit 95 and, if appropriate, further
production parameters as shown schematically at K, to
calculate the best matching shape for the otoplasty, so
that optimum wearing comfort in everyday use is
achieved while maintaining its functionality. If the
CA 02422425 2003-03-05
34
otoplasty to be produced is realized using the
principle set out in section 3), the computer unit 97
determines which otoplasty areas are to be configured
and how in terms of their flexibility, bendability,
compressibilty, etc. At its output, the computer unit
97, as has been stated, controls the production process
99, preferably in this case the production process as
was set out in section 1) as the preferred process.
