IMPROVEMENTS IN TELEPHONE RECEIVERS
Year: 1884

page_text: I WILLIAM ROBERT LAKE of the firm of Haseltine Lake & Co Patent Agents
Southampton Buildings in the County of Middlesex do hereby declare the
nature of my invention for "IMPROVEMENTS IN TELEPHONE RECEIVERS
" to be
as follows:-
This invention relates to telephone receivers and differs from ordinary instru-
ments of this class in that, the coil has no core but has a hollow centre and is
fitted to lie in a non-conducting case.
One face of the coil is substantially level with the face of the case so that the
diaphragm lying on the face of the case may have a proper vibration. Over this
diaphragm, and bearing on its margin, is placed the sound-wave concentrator. Two
binding posts are connected, with the case; and with the posts, are connected the
wires leading respectively from the periphery and from the centre of the coil; the
line and battery wires are also attached to these posts.
According to the said invention I provide a non-conducting case in which is
formed a chamber of suitable dimensions to receive one or more coils of wire formed
with a hollow centre. Where more than one coil is employed, one may be placed
above the other in the said chamber and switches may connect them to attain
greater power. The coils are made of insulated or covered copper wire, or insulated
or covered iron wire, or they may be made in part of insulated or covered copper
wire, and insulated or covered iron wire to form a single coil, or these two kinds
of wire may be coiled separately to form sections of the same roll or coil, and be
connected by the same switches which are employed to connect the two coils lying
one above the other.
The advantage of this compound coil is the attainment of a much greater
plenitude of action than heretofore.
The periphery of the coil is enclosed in hard India-rubber or some suitable
material to hold it in position in the case.
Secured to the face of the case, and bearing on the margin of the diaphragm, is
the sound-wave concentrator of ordinary construction. Attached to the periphery
of the case is a binding post with which the wire leading from the centre of the
[Price Gd.1

page_text: coil is connected; to a second binding post is attached a wire leading from the
periphery of the coil; the first mentioned wire is connected with the battery wire
and the second wire with the transmitter by means of the said posts.
Where two or more coils are employed to attain greater power or capacity, they
are connected by switches, which extend in from the periphery of the case for that
purpose. It has been a customary theory that a coil is inoperative without a core
of iron or steel; the communicator of this invention has however demonstrated that
a coil without a core-in fact with a hollow centre-will not only perform the
desired functions in a receiver but perform those functions in a superior manner,
as compared with the steel or iron magnet cores, thereby utilizing the well know
law of mutual attraction and gravitation which applies equally well to the mole-
cules of all bodies as to the bodies themselves where their equilibrium is disturbed,
for the reason that all sound is produced by decomposition and re-formation of
atmospheric air which produces what is known as sound waves. Now, the sooner
the air recovers its equilibrium after being disturbed the more distinct the sound
will be. Hence a magnet or other device holding the diaphragın beyond the
proper period is detrimental rather than advantageous for transmitting sound
without induction. The vibrations of the diaphragm are produced by the mole-
cular disturbance in the coil by the action of electricity thereon and consequently
the sound produced on the transmitting instrument is duplicated by the receiver,
only less in plenitude.
HASELTINE, LAKE & Co.,
For the Applicant.

page_text: COMPLETE SPECIFICATION.
I, WILLIAM ROBERT LAKE of the firm of Haseltine, Lake & Co, Patent Agents,
Southampton Buildings, in the County of Middlesex do hereby declare the nature
of my invention for IMPROVEMENTS IN TELEPHONE RECEIVERS" 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 telephone receivers and differs from ordinary instru-
ments of this class in that, the coil has no core but has a hollow centre and is
fitted to lie in a non-conducting case.
One face of the coil is substantially level with the face of the case so that the
diaphragm lying on the face of the case may have a proper vibration. Over this
diaphragm, and bearing on its margin, is placed the sound-wave-concentrator. Two
binding posts are connected, with the case; and with the posts, are connected the
wires leading respectively from the periphery and the centre of the coil. The line
and battery wires are also attached to these posts.
In the accompanying drawing
Figure 1 is a central sectional elevation of apparatus embodying my invention.
Figure 2 is a face view of the case and coil, the other parts being removed to
give a clearer view of the construction.
Figure 3 is a perspective view of the coil removed from the case.
A represents the non-conducting case in which is provided a chamber B of suit-
able dimensions to receive one or more coils of wire F formed with a hollow
centre a.
When more than one coil is employed one may be placed above the other in the
chamber B, and switches may connect them to attain greater power.
The coils are made of insulated or covered copper wire, or insulated or covered
iron wire, or they may be made in part of insulated or covered copper wire, and
insulated or covered iron wire to form a single coil, or these two kinds of wire may
be coiled separately to form sections of the same roll or coil, and be. connected by
the same switches which are employed to connect the two coils lying one above the
other.
The advantage of this compound coil is the attainment of a much greater
plenitude of action than heretofore.
The periphery of the coil is enclosed, in hard india-rubber, or some suitable
material to hold it in position in the case.
Secured to the face C of the case A and bearing on the margin of the diaphragm D
is the sound-wave-concentrator E of ordinary construction.
Attached to the periphery of the case A is a binding post G with which the
wire g leading from the centre of the coil is connected. H is also a binding post
to which a wire h leading from the periphery of the coil is connected, the wire g
being connected with the battery wire and the wire h with the transmitter by
means of said posts.
Where two or more coils are employed to attain greater power or capacity, they
are connected by switches (two of which are shown by dotted lines I. J.) which
extend in from the periphery of the case for that purpose. It has been a customary

page_text: theory that a coil is inoperative without a magnet centre of iron or steel; the com-
municator of this invention has, however, demonstrated that a coil without a core,
in fact with a hollow centre will not only perform the desired functions in a
receiver but perform those functions in a superior manner, as compared with the
steel or iron magnet cores; thereby utilizing the well known law of mutual attrac-
tion and gravitation which applies equally well to the molecules of all bodies, as
well as to the bodies themselves where their equilibrium is disturbed, for the reason
that all sound is produced by decomposition and re-formation of atmospheric air
which produces what are known as sound waves. Now, the sooner the air recovers
its equilibrium after being disturbed the more distinct the sound will be. Hence a
magnet or other device holding the diaphragm beyond the proper period is detri-
mental rather than advantageous for transmitting sound without induction. The
vibrations of the diaphragm D are produced by the molecular disturbance in the
coil by the action of electricity thereon, and consequently the sound produced
on the transmitting instrument is duplicated by the receiver, only less in
plenitude.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that
.what I claim is
First In a telephono for receiving audible sounds, the coil F formed with a
hollow centre a and placed in a non-conducting case A, and connected with a
battery and transmitting wires, in combination with the diaphragm D which is
actuated by electricity acting on the coil as specified.
Second A coil formed with a hollow centre and partly of copper wire and partly
of iron wire in sections in the same coil, substantially as set forth.
Daded thin 1All Inc. of 100
HASELTINE, LAKE & Co.,
For the Applicant.