Improvements in Apparatus for Enabling Deaf People to Hear.
Year: 1899

page_text: Date of Application, 4th Apr., 1899-Accepted, 12th Aug., 1899
COMPLETE SPECIFICATION.
Improvements in Apparatus for Enabling Deaf People to Hear.
We, REESE HUTCHISON, Electrical Engineer, of 65, North Commerce Street,
Mobile, Alabama, and JAMES HOWARD WILSON, President of Mobile Light & R. R.
Company, of 400, Government Street, Mobile Alabama, United States of America,
do hereby declare the nature of this invention and in what manner the same is
to be performed to be particularly described and ascertained in and by the
following statement:―
This invention relates to audiphones in general, and has for its object to pro-
vide an efficient instrument to enable deaf persons to hear sounds as they are
heard by people with normal ears, and to train the ears of deaf persons to hear
even without the instrument.
This object has been accomplished by constructing an instrument in which
words and sounds are greatly intensified, and providing means whereby the
intensity of the sounds reproduced may be varied at will by the person using
the instrument, to suit the sensitiveness of his ear.
The drum of the ear, and the general auditory apparatus, of deaf persons are
very sensitive to loud sounds through the instrument hereinafter described, but
with the device for regulating the intensity of these sounds, it is possible to
gradually accustom a deaf person to become used to sounds without causing any
inconvenience to him, and in some instances, persons born deaf and dumb have been
so trained with this instrument that they can now hear very well without the
instrument.
In the accompanying drawings:-
Fig. 1 represents one form of instrument made according to this invention,
the handle being shown in section;
Fig. 2 is a plan of Fig. 1, showing the two main parts of the instrument in
section;
Figs. 3, 4 and 5 are diagrams of circuits to show the principles on which the
instrument may operate;
Fig. 6 is a diagram of circuits of instruments shown in Figs. 1 and 2, and
representing a combination of the principles shown by Figs. 3 and 4;
Fig. 7 is a view of a belt provided with a battery;
Fig. 8 is a diagram of circuits of another form of instrument;
Fig. 9 represents a woman having an instrument such as represented diagram-
matically in Fig. 8, fastened to her head;
Fig. 10 represents a man holding in position an instrument such as shown in
Fig. 1, the conducting wires leading from the battery to the instrument proper
being shown in dotted lines.
"
66
For convenience, the part placed against the ear of the deaf person is herein
called the "ear-piece," although it corresponds somewhat to the receiver" of
a telephone, and the other main part, corresponding somewhat to the
mitter" of a telephone, is called the " receiving instrument" as it receives all
the sounds or words near the deaf person.
trans-
While one of the main points of our invention,-namely, the means for varying
077

page_text: the intensity of the sounds reproduced,-relates to any audiphone, we have
here shown but one form of audiphone, that is, one employing electricity to
augment the sounds, and which may be termed an electrical audiphone.
These audiphones comprise essentially one or two ear-pieces constructed to
act on the principle of the microphone; a receiving instrument; a battery and
suitable electrical connections; and a regulator or dampening device.
Figs. 1 and 2 represent one form of instrument adapted to be carried about for
occasional use, and the handle may be sufficiently small to enable the person to
carry the audiphone in the pocket.
This instrument comprises a handle A, an ear-piece B, a receiving instru-
ment C, and a regulator D. A battery E is carried in any convenient place, as
for instance, in a belt adapted for the purpose, see Figs. 7 and 9, or in a pocket,
hand-satchel or the like. "Connecting wires from the battery may pass through
the coat or waist sleeve and be secured inside the sleeve at the wrist, so that
when the instrument is not in use it can be readily disconnected, as hereinafter
described.
Any suitable form of ear-piece B provided with a diaphragm b, and a receiv-
ing instrument C provided with a diaphragm c, may be used. The principle on
which this instrument operates is as follows:-Sound waves, upon striking the
diaphragm c of the receiving instrument C, produce variations in the current
strength in the circuit, thereby producing a corresponding vibration of the
diaphragm of the car-piece B. This action is a microphonic one, but the con-
struction of the special parts renders this instrument not only very sensitive, but
especially adapted to the particular use to which it is to be put. The sounds
reproduced by the diaphragm are greatly intensified, and means are provided
for varying the strength of the current, or for dampening the vibrations of the
diaphragm either of the ear-piece or of the receiving instrument.
If a dampening device is used any suitable construction may be employed, and
as an example only, we have shown in Fig. 2, a lever F in the form of a spring
blade provided with a pad or cushion f of cloth or the like, and secured to the
casing of the receiving instrument C. This pad f is adapted to be pressed
more or less against the diaphragm c, by the thumb-screw f¹. We do not limit
ourselves to this special form of dampening device and although it is shown
applied to the diaphragm of the receiving instrument, it may be placed in the
ear-piece.
Its
Instead of a dampering device, (or even in addition thereto), we preferably
employ a device which we herein term a regulator," that is adapted to vary
the effect of the electric current. This regulator I may be placed on the top
of the handle, as shown in Fig. 1, on the back of the ear-piece, as shown in the
diagram Fig. 8, on the belt, or in any other convenient place in the circuit.
action may be on any of the following principles, or any combination thereof.
Referring to diagram, Fig. 3, suppose the circuit to include the ear-piece B,
receiving instrument C, battery E and a resistance X. If, with given battery
strength, the handle X is placed on contact point of resistance X the
sensibility of the instrument B is at its maximum. If handle X is placed on
contact point 2 then one coil of resistance X is cut into the circuit, thereby
lessening the strength of the current and reducing the efficiency of the instrument.
If more resistance coils are cut in by handle X¹, the sensibility is decreased
proportionately.
Another principle is represented by diagram, Fig. 4. A piece of soft iron, Y,
has wound thereon many turns of a certain sized insulating copper wire, y, and by
placing the handle Y of the switch upon the contact point y2, the current from
the battery E in passing through the coils y will produce a certain magnetic
strength upon core Y. If a coil y of similar wire is then wound on, but in a
reverse direction from that of coil y, when the handle Y¹ is placed upon button y
the current is sent through both coils y, and y, as they are then connected in
series. The magnetic influence of coil y* being reverse to that of coil y, the mag-

page_text: netic strength of core Y is thereby lessened. If more coils are similarly wound
on and cut in, in opposition to coil y, the strength of core Y is inversely decreased
in proportion to the number of coils added, not only due to the converse magnetic
effect, but also to the decrease of current due to the resistance of these extra
coils.
Again referring to this diagram, Fig. 4, if these reverse coils y are of con-
ducting wire having a high electrical resistance, such as German silver, then
these reverse coils will act to cut down the current as well as to reverse the
magnetizing effect.
Still another principle is shown in diagram, Fig. 5. The core Z is magnetized
by battery E with given strength. If the coils of a variable shunt are cut
in around the terminals of the winding, the strength of the core Z will be
diminished inversely as the amount of wire cut in increases.
The varying of the sensibility of the instruments may be made in various
other ways, but the arrangements represented by Figs. 3, 4 and 6, lighten the
load on the battery as the sensibility decreases, thereby lengthening the life of
the battery.
Although any suitable form of ear-piece may be used, we prefer that shown in
Fig. 2, which constitutes a very powerful and efficient instrument. To the
shell of vulcanite or other non-conducting material, is secured the core Y.
formed in the shape shown, in one piece, of finely annealed soft iron. The wire
on bobbins y of core Y forms part of the main circuit. Outside of these bobbins,
coils y, y, are wound in a reverse direction to that of the coils of the bobbins y.
A thin iron diaphragm bis held in place by the insulating cover
An efficient form of receiving instrument is shown in Fig. 2, although we do
not limit ourselves to this special form. The diaphragm c, of proper material
to respond to sound waves projected thereon through the funnel, is secured in
a frame formed of two circular stampings of convenient shape, such as shown.
Secured to the inner side of the diaphragm c is a variable contact rigidly held
in place by the stanchion secured to the frame or casing e', but electrically
insulated therefrom. This variable contact is preferably in the form of two
electrodes, c,, of compressed carbon, having their opposing circumferential
edges grooved as shown, for the purpose of retaining rings c, of flimsy woolen
or other suitable fabric, to hold granulated carbon in the space between the
electrodes. This ring does not perceptibly effect the sensibility of the instru-
ment to respond to sound waves.
The car-piece B and receiving instrument C may be secured to the handle A
in any suitable manner. As shown in the drawings, the ear-piece is rigidly
mounted on the handle by means of the bent arm h, and the receiving instrument
secured to the bent arm h', which latter is so mounted at the back of the ear-
piece as to be capable of being turned from the position shown in full lines,
It is evident that the mounting may
Figs. 1 and 2, to that shown in dotted lines.
be reversed, that is, the ear-piece may be mounted to turn on the receiving
instrument, and the receiving instrument secured to the handle, to obtain the same
result, namely to so mount the instruments on the handle that their relative
positions may be readily changed to suit the instrument for either ear, for sounds
The nuts and washers are so
from the front or from the rear of the user.
adjusted that in whatever position the movable part is placed, it will be main-
tained there by friction.
The handle is of insulating material, and is made hollow to permit the inser-
tion of a bobbin on which are wound coils of a resistance X, although these
resistance coils may be anywhere else in the circuit. The lower part of the
handle is provided with two metal sockets a, a, Fig. 1, adapted to receive the
plugs e, e, at the ends of the wires connected with the battery. When these
plugs are inserted in the sockets they are given a half turn to bring the semi-
circular flanges e, e³, into the semicircular recesses a², a³, of the handle, to securely

page_text: retain the plugs. Insulated conducting wires, c, e, lead from the sockets a, a',
to the instruments B, C, and may pass through a hole in the center of the
resistance bobbin.
The regulator D is shown in Fig. 1 as mounted at the top of the handle. It
consists of a disc d adapted to be rotated by the thumb or finger, and is provided
on its under side with a contact piece preferably in the form of a spring blade.
A series of contact points a¹, &, etc. are mounted in an arc on the top of the
handle A, so that when the disc d is rotated the contact piece may contact
successively with the different points x¹, x³, etc.
This special form of regulator is not essential, as the disc d may be replaced
by a lever as shown in the diagram figures. And although this regulator is
shown on the handle in Fig. 1, it may be placed in any other convenient position.
It may be separated for instance, from the instruments, and be placed where it
may be operated by the free hand, or it may be placed on the back of the ear.
piece, as shown in the diagram, Fig. 8.
The connections cannot be well shown in Fig. 1, but one arrangement of
circuits is shown in diagram, Fig. 6, as follows:-Wire 1 from battery E con-
nects with the diaphragm c and electrode of receiver C, the other electrode c
of the receiving instrument being connected by wire 2 to the regulator disc or
handle D. Button or contact point a¹ is connected to the main wire leading to
coils y of the ear-piece B and thence to the battery E through wire 3.
If reverse coils are not to be used, the coils of resistance X,
only, are connected to the points a¹, №², etc., or if the resistance coils are not to
be used, the coils y, only, are connected to points 1, 2, etc. However, as
shown in Fig. 6 (and Figs. 1 and 2) both reverse coils 4 and resistance coils X
are used, one coil y and one coil of resistance X being connected in series, and
to two contact points and 2, as shown. A second reverse coil and a second
resistance coil are connected in series to contact points 2 and 3, and so on.
It will be evident that if regulator handle D is turned so that it contacts with
point, all the reverse coils and the coils of resistance X will be cut out of
the circuit and the instrument is at its maximum power, and that as the regulator
is turned to cut in more coils (reverse and resistance) the power decreases as
explained.
The contact point of the handle (or contact piece d', Fig. 1), of the regulator D
should be sufficiently large, and the contact points x1, x2, etc., sufficiently near
together to make it impossible for the handle (or contact piece d¹) to pass from
one contact point without touching the next contact point. Without this pre-
caution, the circuit would be broken in passing from one button or contact
point to the next, thus producing a very disagreeable and injurious effect upon
the ear.
As it is not necessary that the battery shall always be in circuit, in order to
keep the circuit open when the instrument is not in use, and also to prevent
the regulator from being carelessly left at the point of greatest sensibility,
whereby any extra loud noise taking place when the instrument is first applied
might hurt the ear, the regulator disc or handle is provided with a suitable
spring tending to return and hold the regulator at the zero points, which opens
the circuit. When the instrument is to be used the disc or handle is first placed
on the point next to zero, point 7, of least sensibility, and then the user can turn
the disc or handle to adjust the regulator D to the proper degree of sensibility.
This regulator, to vary at will the sensibility of the audiphone, is of the utmost
importance, as, without it, the instrument could not be used by certain persons,
due to the severe pain caused by the too sensitive action thereof upon the unused
ear.
The belt R, Fig. 7, is well adapted to carry the battery E, and is provided with
binding posts r, and may be provided with button-holes r¹, or straps or the like,
to secure the belt to the clothing of the person using the instrument.
Fig. 10 represents a man holding a portable instrument, such as shown in

page_text: Figs. 1 and 2, to his ear, and also shows in dotted lines a battery belt in place,
and the connecting wires.
Fig. 9 represents a woman wearing a head attachment provided with an ear-
piece for each ear, to one of which ear-pieces is attached a receiving instrument.
A handle is unnecessary with this arrangement. This form is preferable for
such use as when a deaf person is being taught. The receiving instrument, how-
ever, may be held by the teacher, the head-piece carrying only the ear-pieces.
A diagram of circuits for either such arrangement is shown in Fig. 8.
Each ear-piece is provided with its own separate regulator D', which may cut
in or out resistance coils, as diagrammatically shown in connection with the lower
ear-piece of this figure, and in Fig. 3, or may cut in and out reverse coils as
shown in Fig. 4, or may shunt the current as shown in Fig. 5, or may act on
any combination of these principles.
Here is also shown a device for cutting in and out the successive cells of a
battery, which may be under the control of the teacher. When the handle S is
on zero buttons, the circuit is open, when on button s', one cell of the battery E
is cut in, ons two cells, and so on.
This battery controlling device may also be arranged to change the battery
connections from series to multiple, and thus vary the amperage.
The handle of the regulator 11 may be adapted to return and normally be
held at a zero point, or at the point of least sensibility not on zero, but in cases
where a special regulator for the main current is used, it is preferable to have
the handles of the separate car-piece regulators adapted to remain at any desired
point, so that when the ear-pieces have been adjusted to suit each ear, the regula-
tors may be left in the adjusted position; and the main current regulator act
as a common controller.
It is evident that a second receiving instrument C, shown in dotted lines in
Fig. 8, may be inserted in the circuit, to be used by the pupil, so that when he
repeats after the teacher into the receiving instrument C¹, he may hear his own
voice and thus distinguish between his expression and that of his teacher.
It is also evident that a series of outfits for pupils (each comprising a pair of
car-pieces and a corresponding receiving instrument) may be connected
to a separate receiving instrument and main current regulator for
the teacher, and suitable switches inserted, whereby as soon as a pupil comes
into the class he may switch his instrument into the main circuit, (or this may
be done automatically when he takes his place or takes up his instrument,) and
also switches to cut each pupil's outfit into or out of circuit with the teacher's
instrument, whereby any outfit may be switched off by itself or isolated so that
the pupil may practice by himself without interfering with the other scholars.
Having now described and ascertained the nature and object of our said inven-
tion and in what manner the same is to be performed, we wish it to be understood
that we do not limit ourselves to the special form of instruments shown, but we
declare that what we claim and desire to secure by Letters Patent is:-
1. The combination of an audiphone for the use of deaf persons, with means
for varying at will the intensity of sounds reproduced in the audiphone, to suit
the sensitiveness of the car of the deaf person.
2. The combination of an audiphone having a microphonic action, for the use
of deaf persons, with a regulator to control the intensity of sounds in the instru-
ment.
3. In an audiphone, the combination of an electrical circuit, a receiving instru-
ment and an ear-piece in the said circuit, the said ear-piece adapted to reproduce
sounds received in the said receiving instrument, and provided with a regulator
adapted to remain at any desired point of adjustment, a main current regulator
and means for normally returning and holding the said main current regulator
at a zero point to open the circuit.
4. An audiphone provided with a vibrating diaphragm, in combination with

page_text: means for dampening more or less the vibrations of said diaphragm at the will
of the user.
5. In an
audiphone, an electrical ear-piece provided with a diaphragm and elec-
trical means for operating the same, in combination with a handle supporting
the ear-piece, and a device on the said handle to regulate at will the intensity
and effect of the electric current, substantially as specified.
6. In an audiphone, an ear-piece provided with a diaphragm and electrical
means for operating the same, with a regulator for varying the sensibility of the
car-piece, the said regulator being provided with contact points and a movable
contact piece, coils of wire connected with the said contact points, and con-
nections whereby said movable piece may cut in or out of the electrical circuit
one or more of said coils, substantially as specified.
7. An electric circuit, an electro magnet comprising a soft iron core, coils
wound on said core in opposite directions but in series in the electric circuit,
and means for cutting in and out of the circuit any of the said coils, substantially
as specified.
8. An electric circuit, an electro-magnet comprising a soft iron core, coils
wound on said core in one direction and reverse coils of high electrical resistance
wire wound on the same core in the opposite direction, the said coils being in
series in the said electrical circuit, and means for cutting in and out of the circuit
the said reverse coils, substantially as specified.
9. In an audiphone, an electrical car-piece provided with a diaphragm and
electrical means for operating the same, a device for regulating the sensibility of
the instrument at will and means for normally holding the said device at the
point of least sensibility.
10. In an audiphone, an ear-piece, a receiving instrument and a handle, the
said ear-piece and receiving instrument being so mounted on the said handle
that the position of one may be readily changed in relation to that of the other,
substantially as specified.
11. An audiphone having a microphonic action, and provided with a regulator
to vary the intensity of sounds reproduced therein, the said regulator operating
on any of the principles herein shown and described, or on a combination of
any of them.
12. In an audiphone, the combination of a receiving instrument, and two
ear-pieces adapted to reproduce the sounds received in the said receiving instru-
ment, each air-piece being provided with a regulator adapted to separately con-
trol the intensity of sounds reproduced therein, to suit the sensitiveness of each
ear of the deaf person.
GEO. DAVIES & SON,
Agents for the Applicants, St. Ann's Square, Manchester.