Note: Descriptions are shown in the official language in which they were submitted.
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1
HEARING AID PLACED IN THE EAR AND METHOD FOR PRODUCING SAME
The present invention relates to an in-the-ear hearing device with an
electric/acoustic transducer arrangement. Furthermore, the invention relates
to a
method for producing an in-the-ear hearing device.
In-the-ear hearing devices are known to suffer from
problems of soiling, in particular of the acoustic output
of the device facing the ear drum. This soiling leads to
impairment of the effect of the hearing device and makes
it necessary to clean the hearing device periodically.
In this respect, the aperture usually provided in the
hearing device housing, coupled as an acoustic output to
the output of the electric/acoustic transducer, leads to
significant cleaning problems.
It is known from EP 0 548 580 to provide an in-the-ear
hearing device with a diaphragm which closes off the
housing and is coupled to the loudspeaker drive motor in
a way similar to the actual loudspeaker diaphragm. This
makes the structural design of the hearing device
relatively complicated and so too, in particular, the
measures which have to be taken to couple said diaphragm
to the loudspeaker drive and ensure that this diaphragm
is not impaired during cleaning.
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2
It is an object of the present invention to eliminate the
stated disadvantages of the already known solution and at
the same time propose an in-the-ear hearing device which
makes allowance for the cleaning needs in a structurally
simple manner.
According to the present invention, there is provided a method of
manufacturing a
hearing device, comprising the steps of:
providing a hearing aid housing having an opening;
providing an electric/acoustic transducer;
providing a support plate forming a blind hole having a membrane as a base;
inserting said transducer into said blind hole;
bringing said housing and said support plate together such that a portion of
said transducer enters through said opening of said housing;
bonding said housing to said support plate; and
trimming an excess portion of said support plate.
According to the present invention, there is also provided a method of
manufacturing a hearing device, comprising the steps of:
providing a housing having an opening;
providing an electric/acoustic transducer;
providing a support plate forming a blind hole having a membrane as a base;
inserting said transducer into said blind hole, wherein an extending portion
of
said transducer extends from said blind hole out of said base plate;
bringing said housing and said support plate together such that said
extending portion enters through said opening of said housing;
bonding said housing to said support plate; and
trimming an excess portion of said support plate.
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2a
According to the present invention, there is also provided a method of
manufacturing a hearing device, comprising the steps of:
providing a housing having an opening;
providing an electric/acoustic transducer;
providing a support plate forming a blind hole having a membrane as a base;
inserting said transducer into said blind hole, wherein an extending portion
of
said transducer extends from said blind hole out of said base plate;
bringing said housing and said support plate together such that said
extending portion enters through said opening of said housing;
bonding said housing to said support plate; and
trimming an excess portion of said support plate to continue a contour of:
said housing and to form an acoustic opening to be utilized as an
acoustic output of said hearing device, wherein
said membrane forms a freely vibrating membrane covering said
acoustic opening.
According to the present invention, there is also provided a method of
manufacturing a hearing device, said hearing device comprising:
a housing including a part forming an acoustic opening;
an electric/acoustic transducer including:
a diaphragm;
an electric drive coupled to said diaphragm; and
an encapsulation comprising said part of said hearing aid housing; and
a freely vibrating membrane at least substantially flush with an outer surface
of said part and facing a surrounding of said hearing aid, wherein
said acoustic opening establishes acoustical communication between said
diaphragm and the surrounding of said hearing aid, and further wherein
said acoustic opening is covered by said freely vibrating membrane; wherein
said method comprises the steps of:
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2b
providing a support plate forming a blind hole having said membrane as a
base;
inserting said transducer into said blind hole, wherein an extending portion
of
said transducer extends from said blind hole out of said base plate;
bringing said housing and said support plate together such that said
extending portion enters said housing;
bonding said housing to said support plate; and
trimming an excess portion of said support plate to form said part.
According to the present invention, there is also provided a method of
manufacturing a hearing device, comprising the steps of:
providing a hearing aid housing having an opening;
providing an electric/acoustic transducer;
providing a support plate forming a blind hole having a membrane as a base;
inserting said transducer into said blind hole, wherein said transducer is
held
within said blind hole by frictional means;
bringing said housing and said support plate together such that a portion of
said transducer enters through said opening of said housing, wherein said
transducer is held within said housing by frictional means;
bonding said housing to said sup.port plate; and
trimming an excess portion of said support plate.
According to the present invention, there is also provided a hearing device
comprising:
a hearing aid housing including a wall with an inner surface and with an
outer surface facing towards a surrounding of said device;
a transducer including an encapsulation, said encapsulation comprising
either a part of said wall or having an encapsulation wall portion being
mounted
along a section of said wall;
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2c
an opening from the inside of said encapsulation through said wall;
wherein said part of said wall or said encapsulation wall portion has a freely
vibrating portion, and wherein said opening establishes acoustical
communication
between the inside of said encapsulation and the surrounding of said hearing
device and wherein said opening is covered by said freely vibrating portion.
According to the present invention, there is also provided a hearing device
comprising:
a hearing device housing including a part;
a transducer with an acoustical port communicating with a surrounding of
said device via an acoustical opening in said part;
a freely vibrating membrane covering said opening and being removably
applied and elastically held to said part by elastically slipping said
membrane over
said part.
According to the present invention, there is also provided a hearing device
comprising:
a hearing device housing including a wall with an inner surface and with an
outer surface facing towards a surrounding of said device, said housing
forming a
first opening;
an encapsulation within said housing for encapsulating a transducer, said
encapsulation being mounted _ to said inner surface of said wall and forming a
second opening, wherein said second opening communicates with said first
opening; and;
a part including a freely vibrating membrane at least substantially in plane
with said outer surface of said wall, wherein said first and said second
openings
establish acoustical communication between an inside of said encapsulation and
the surrounding of said hearing device, and wherein said first opening is
covered by
said freely vibrating membrane, and wherein
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2d
said part is in direct contact or integral with said encapsulation.
According to the present invention, there is also provided a hearing device
comprising:
a hearing device housing including a wall with an inner surface and with an
outer surface facing towards a surrounding of said device;
a transducer;
an encapsulation for encapsulating said transducer, said encapsulation
being mounted to said inner surface of said wall and forming an opening from
an
inside of said encapsulation through said wall; and
a part including a freely vibrating membrane at least substantially in plane
with said outer surface of said wall, wherein said opening establishes
acoustical
communication between the inside of said encapsulation and the surrounding of
said hearing device and wherein said opening is covered by said freely
vibrating
membrane, and wherein
said part is in direct contact or integral with said encapsulation.
Preferably, this is achieved by the acoustic output of the electric/acoustic
transducer arrangement on the in-the-ear hearing device being separated from
the
surroundings of the device by means of a diaphragm which is arranged in a
freely
vibrating manner. In this respect, it was recognized that appropriate design
of the
acoustically effective spaces on the hearing device and of the diaphragm
characteristic, in terms of acoustic impedance adaptation, can achieve the
effect
that such a freely vibrating diaphragm has virtually no effect on the acoustic
transmission behaviour of the hearing device on the output side of said
transducer,
i.e. said diaphragm is acoustically transparent.
If desired, it is also possible with such a diaphragm to achieve desired
damping.
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In a further preferred embodiment of the in-the-ear
hearing device according to the invention, at least the
freely vibrating element of the diaphragm is produced
from a single material, is preferably elastomeric, for
example made of latex or of silicone rubber.
Furthermore, in a preferred embodiment, the diaphragm
provided according to the invention has a constant
thickness, at least at the element referred to.
Consequently, the structure for the hearing device is
increased in height only inconsequentially by provision
of said diaphragm. The diaphragm material used with
preference, such as latex or silicone for example, is
very inexpensive and is produced with a uniform, low
thickness, is resistant and is harmless when in contact
with living tissue.
In a particularly preferred embodiment, said diaphragm is
arranged in the direct region of the device output,
thereby obviating the need for shaped recesses and
indentations on the device, which make cleaning
problematical, in particular in the region of its
acoustic output. Furthermore, the acoustic output of the
transducer arrangement may in this case be connected to
the acoustic output aperture of the hearing device
housing by means of a tubular stub, although, in a
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4
preferred embodiment, the acoustic output of the electric/acoustic transducer
arrangement is arranged directly in the region of the output aperture of the
hearing
device housing.
In a preferable embodiment, which is extremely advantageous with regard to the
production of the hearing device, the output aperture of the hearing device is
formed by a cover element connected in a plate-shaped manner to the remaining
hearing device housing, such as welded or adhesively bonded for example. In
this
case, it is further preferred for the diaphragm which closes the output
aperture of
the device to be integrally formed with said element or provided as a separate
part
on said element. The diaphragm may, if appropriate, also be placed in a hose-
like
manner over the hearing device housing.
If in this case said element is integrally formed with the diaphragm, the
material-
specific requirements for the diaphragm must also be imposed on the element.
This
element is then preferably produced from elastomeric material, for example
from
latex or silicone.
Preferably, the transducer arrangement is positioned in a blind aperture in a
support plate, the base element of which is formed by a diaphragm. By relative
movement of the support plate and the hearing device housing, the transducer
arrangement is then introduced from the end forming the acoustic output of the
hearing device housing into the hearing device housing. Then, the support
plate is
connected to the hearing device housing, for example is adhesively bonded or
welded, and after that the support plate is molded into shape along the
contour of
the hearing device housing.
This procedure is extremely well-suited for automating
the assembling of the in-the the-ear hearing device
housing and electric/acoustic transducer arrangement and
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diaphragm.
In a preferred embodiment of the production method
according to the invention, the diaphragm is integrally
formed with the support plate, whereby the support plate
is preferably made of an elastomeric material, for
example of latex or silicone, or the diaphragm is
applied, such as adhesively, as a film-like element to
the support plate, which initially has through-openings,
the blind apertures only being formed at this stage.
To this day it is customary to perform the assembly of
in-the-ear hearing device housings and electric/acoustic
transducer arrangement [sic] manually. This is because
it is necessary to avoid formation between the
loudspeaker in the electric/acoustic transducer
arrangement and the device housing of an acoustically
effective bridge, which leads to feedback of the acoustic
signals directly or via the surrounding ear tissue to the
acoustic/electric transducer on the input side of the
device. Therefore, as mentioned, it is customary for the
transducer arrangement to be introduced manually in the
hearing device housing, at a distance from the latter on
all sides, and positioned there.
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From a further aspect, the present invention then has the purpose of
significantly
reducing the production effort necessary for this. Preferably, this is
achieved in
principle by the transducer arrangement being introduced into the hearing
device
housing in an automated manner. As a difference from the conventional
procedure,
according to which the transducer arrangement is pushed in from "above"
through
the hearing device housing to the acoustic output element of the latter,
according to
a much preferred embodiment of said production method the transducer
arrangement is
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introduced into said housing through an aperture forming
the acoustic output of the hearing device housing. In a
much preferred embodiment, this takes place by the
transducer arrangement being positioned in a receiving
aperture in a support plate, then, by relative movement
of the support plate with respect to the hearing device
housing, the transducer arrangement being introduced from
the end forming the acoustic output of the hearing device
housing into said housing. In particular in the further
preferred embodiment, according to which the support
plate is then connected to the hearing device housing,
such as adhesively bonded or welded for example, and
after that the support plate is molded into shape along
the outer contour of the hearing device, the effect is
achieved that the transducer arrangement is positioned in
said support plate and remains secured in place, and
consequently the positioning of the transducer
arrangement in the device housing becomes a question of
the exact infeeding movement of the device housing and
support plate. As mentioned, this procedure is ideally
suited for automated assembly.
The invention is explained below on the basis of figures,
in which:
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figure 1 shows the diagram of a transducer arrangement
which is formed as a module;
figure 2 shows in a diagrammatically simplifying form a
longitudinal section through the transducer
arrangement in an actual embodiment;
figure 2a shows a further embodiment of the transducer
according to figure 2, diagrammatically, with
the diaphragm according to the invention;
figure 3 shows, again diagrammatically, the installation
of a transducer arrangement on an in-the-ear
hearing device according to the invention with
the diaphragm provided according to the
invention;
figure 4 shows in a representation analogous to that of
figure 3 a further possible way of installing a
transducer arrangement with the diaphragm
according to the invention on an in-the-ear
hearing device according to the invention;
figure 5 shows in a representation analogous to figures
3 and 4 a further preferred design variant of
the element forming the acoustic device output
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of an in-the-ear hearing device according to the
invention, and
figures 6(a)
to 6(c) diagrammatically show the sequence of a
production method according to the invention for
an in-the-ear hearing device with regard to
assembling the electric/acoustic transducer
arrangement and the device housing.
Figure 1 diagrammatically shows a transducer module for
explaining the acoustic coupling principles. The
transducer module 1 comprises a loudspeaker housing 3, in
which the loudspeaker diaphragm 5 is mounted. The
loudspeaker diaphragm 5 is excited by a motor drive 7,
which is only diagrammatically represented. In the
loudspeaker housing 3, a front chamber R1 and a rear
chamber R2 are formed by the loudspeaker diaphragm 5. One
of the two said chambers, for example the rear chamber R2,
is acoustically coupled by acoustic coupling-out
apertures 9 to an intermediate space 11, formed between
the loudspeaker housing 3 and an enclosure 13. The
enclosure 13, and consequently the intermediate space 11,
surround the loudspeaker housing 3 essentially entirely,
apart from resilient bearing elements 15, by means of
which the loudspeaker housing is kept at a distance,
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mounted essentially in a "floating" manner, within the
enclosure 13. According to figure 1, the front chamber R1
is connected to the acoustic output AA of the transducer
module 1.
With the design shown, an acoustic decoupling of the
effect of the loudspeaker on the enclosure 13 is achieved
on account of the essentially floating mounting of the
loudspeaker housing 3 in the enclosure 13. Furthermore,
by significantly enlarging the rear diaphragm chamber R2,
that is including the intermediate space 11, the acoustic
behavior of the transducer module 1 is significantly
improved as compared with that of the loudspeaker
arrangement in the housing 3: the bass response of the
transducer module is raised by several dB as compared
with the bass response of the loudspeaker arrangement in
the housing 3.
In a preferred embodiment of the transducer module 1, a
diaphragm is provided at the acoustic output AA of this
module itself, as diagrammatically represented by 17.
Apart from being fixed at its edge, the diaphragm 17
vibrates freely. It preferably consists of a homogeneous
material phase, preferably an elastomeric material, for
example latex or silicone rubber, and, in a further
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preferred feature, has a constant thickness of about 100
m, preferably at most 0.09 mm.
By matching the acoustic impedance of the intermediate
space 11 with the chamber R2, the chamber R1 as far as the
diaphragm 17, the diaphragm 17 and any acoustic conductor
that might be provided to propagate further toward the
surroundings U of the transducer module 1, the effect is
achieved that the diaphragm 17 is practically
acoustically transparent.
Figure 2 shows a cross section through an embodiment of
the transducer module 1. The reference symbols already
used in the diagrammatic representation of figure 1 are
also used here. The loudspeaker housing 3 with the
coupling apertures 9 is mounted on the enclosure 13 by
means of elastomeric bearing blocks 19. The enclosure 13
is formed by a cup 20, which preferably acts at the same
time as a magnetic shield and, for this purpose,
preferably consists of metal. In any event, the cup 20
is preferably metallic. The cup 20 is closed by a cover
part 22. The diaphragm 17, already presented in figure
1, may in this case be mounted directly on the cover part
22. At the same time, the cover part 22 and the
diaphragm 17 may well be integrally formed, in which case
however the material of the cover part 22 must meet the
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material requirements for the diaphragm, for instance
with respect to elastomeric behavior. For example, the
entire part 22 is then made of latex or silicone rubber.
Otherwise, however, the diaphragm 17 is anchored as a
separate part on the cover part 22. The diaphragm 17 may
also be provided between the acoustic output A3 in the
loudspeaker housing 3 and the clear aperture in the part
22. Preferably, however, as represented in figure 2, the
diaphragm 17 is provided flush with the clear aperture in
the cover part 22, whereby the complete transducer module
1 appears as a self-contained, encapsulated unit and can
be readily cleaned. This is especially significant if,
as still to be shown, the output AA of the transducer
module 1 lies directly at the acoustic output of a
hearing device.
The transducer module or its enclosure 13 may be cubic,
cylindrical or designed in some other form of essentially
any desired kind, provided that the required intermediate
space 11, essentially enclosing the loudspeaker housing
3, is formed between the loudspeaker housing 3 and the
enclosure 13. On the basis of the explanations relating
to figure 2, figure 2a shows a further embodiment in a
merely diagrammatic form. Here, an elastomeric hose 17a
is pulled over the enclosure 13. Said hose at the same
time forms the cover part 22 and diaphragm 17.
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Figure 3 diagrammatically shows the segment of an in-the-
ear hearing device 24 with the acoustic output aperture
A24. The transducer module 1, designed as shown in
figures 1, 2 and 2a, is installed within the hearing-
device housing 26, to be precise in that it is secured
and positioned in the housing 26 of the hearing device in
a form-fitting or frictionally locking manner, as
diagrammatically represented by the securing and
positioning clips 28 in figure 3. This is made possible
by the acoustic decoupling of the outer enclosure 13 with
respect to the loudspeaker housing 3 provided on the
transducer module explained with reference to figures 1,
2 and 2a.
Apart from this, the- design of the in-the-ear hearing
device shown in figure 3 is essentially as already known,
in that the acoustic output of the transducer module 1 is
connected to the acoustic output aperture A24 of the
device via a tubular stub 30.
The electronic components and the input-side
acoustic/electric transducer arrangement on the in-the-
ear hearing device 24 with the housing 26 are not
represented in figure 3 and the further figures because
they are not essential for the invention.
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As figure 3 further shows, the diaphragm 17 provided in
the preferred embodiment is installed in the direct
region of the acoustic output A24 on the hearing-device
housing 26.
According to figure 4, the transducer module 1 is fitted
in a form-fitting or frictionally locking manner directly
in the region of the acoustic output A24 of the hearing
device 24 or of the housing 26, as represented by the
diagrammatically shown securing means 28a. In a
preferred embodiment, the freely vibrating diaphragm 17
is provided at the end.
According to figure 5, the housing 26 of the in-the-ear
hearing device 24 is formed on the one hand by a main
housing part 24a, but at the end a cover part 24b is
placed in a plate-like manner on the part 24a, glued or
welded to the part 24a. A transducer module 1 as
described in relation to figures 1 and 2, or directly the
loudspeaker housing of a hitherto known loudspeaker
arrangement, in figure 5 both denoted together by 30, is
seated in the output aperture 32 of the cover part 24b
and is secured there, such as by clamping, gluing etc.
if the transducer module represented in a general manner
by 30 in figure 5 is one with an enclosure, i.e. is
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designed in the manner of figures 1, 2 or 2a, positioning
and fixing members may be provided for this transducer
module 1 within the hearing-device housing 26, as in turn
diagrammatically indicated by 28.
The diaphragm of the type described above, or a
preferably provided diaphragm, is also represented by 17
in figure 5, in a preferred position. As still to become
evident, the design according to figure 5 has major
advantages, whether for hearing devices with a transducer
module according to figures 1, 2, 2a or for hearing
devices with hitherto known transducer arrangements, i.e.
with a loudspeaker housing directly on the outside.
Furthermore, the diaphragm 17 may be integrally formed
with the part 24b, in particular because, with the part
24b separate from the rest of the housing 26, the choice
of material for this part can be matched to the
requirements of the diaphragm 17.
Figures 6(a) to 6(c) diagrammatically show the sequence
of a preferred production method for in-the-ear hearing
devices.
According to figure 6(a), receiving apertures 36,
preferably in the form of blind apertures, are provided
in a support plate 34 and the transducer arrangements 30
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to be provided on in-the-ear hearing devices are inserted
in said apertures. If the transducer arrangements 30 are
of a known type, i.e. with an external loudspeaker
housing and without an enclosure according to figures 1,
2, 2a, the transducer arrangements 30 are preferably
firmly anchored in the support plate 34, for instance are
adhesively bonded to it. If, however, they are
transducer arrangements with an external enclosure
according to figures 1, 2, 2a, the arrangements 30 need
not be firmly secured in the support plate 34, because
they can, as has been shown, be secured in the
corresponding device housings 24a in a form-fitting or
frictionally locking manner, as indicated with dashed
lines by 28b. Of significance with regard to the
technical aspects of the method is firstly that, due to
relative movement of the plate 34 with the transducer
arrangements 30 and a corresponding number of housing
parts 24a, the transducer arrangements 30 are not pushed
in the customary manner from above, but from below, into
the elements of the housing parts 24a facing the acoustic
output.
In the case in which the transducer arrangements 30 are
designed with enclosures, once the transducer
arrangements 30 have been pushed into the housings 26 in
a securing manner, the support plate 34 can be removed,
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the transducer arrangements or modules being secured and
positioned in the housings 24a. However, in the case
concerning transducer arrangements without enclosures,
the transducers 30 remain in the apertures 36 of the
plate 34 provided for them. The plate 34 is connected,
for example adhesively bonded or welded, to the housing
24a and, based on the position according to figure 6(b),
the plate 34 is subsequently trimmed to become flush with
the outer housing contour (transition to figure 6(c)).
This produces the in-the-ear hearing device as
represented in figure 5. However, this procedure is also
used with preference for transducer modules designed
according to figures 1, 2, 2a, i.e. with enclosures.
It is thus evident from viewing figure 6 that this
procedure is extremely well-suited for installing the
diaphragm 17, or a further diaphragm preferably to be
provided, at the same time as a guard to protect the
acoustic device output from soiling and to ensure simple
cleaning. For this purpose, the base plate 34 according
to figure 6(a) of the apertures 36, preferably formed as
blind apertures, is formed directly as the diaphragm.
This takes place by either the material of the support
plate 34 been chosen to meet the requirements for the
diaphragm material, and consequently the diaphragm being
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formed integrally with the plate 34, or, as represented
by dashed lines in figure 6(a), by the blind apertures 36
only being formed by laminating the support plate 34, the
apertures 36 still being open right through, with a
sheet-like layer 34b which then forms the diaphragm 17
according to figure 5.
The production method represented makes it possible to
fit both transducer modules according to figures 1, 2, 2a
and conventional transducer arrangements, i.e. with an
external loudspeaker housing, in the in-the-ear hearing-
device housing without meticulous positioning
manipulations. This can be carried out from that side of
the housing on which the acoustic output lies.
Consequently, assembling of a kind which is automated to
the greatest extent is made possible. If, as preferred,
the acoustic output of the hearing device is to be
designed such that it is protected against soiling from
the surroundings and allows good cleaning, this at the
same time provides the possibility, as explained, of also
installing a covering diaphragm 17.