IMPROVEMENTS IN APPARATUS FOR TRANSMITTING AND RECEIVING ELECTRICAL SIGNALS
Year: 1885

page_text: This Specification was, upon the 15th day of April 1887, amended under
Sections 18 to 21 of the Patents, Designs, and Trade Marks Act, 1883.
"
Electrical Signals.
I JOHN CLAYTON MEWBURN of 169 Fleet Street, in the City of London, Fellow
of the Institute of Patent Agents do hereby declare the nature of my invention
for IMPROVEMENTS IN APPARATUS FOR TRANSMITTING AND RECEIVING ELECTRICAL
SIGNALS" to be as follows:-
This invention has for its primary object the construction of apparatus for
transmitting electrical signals to a distanco, and consists in means of producing the
requisite current for this purpose by one or more coils or bobbins which have a to
and fro motion imparted to them in a magnetic field by means of a spring or
springs or their equivalent made to vibrate by being moved by the application of
manual power out of the normal or central position and then released or let go.
The spring carries the coil (or it may carry the magnet instead of the coil) and
transforms the power applied into electricity by imparting the said to and fro or
vibrating motion to the coil (or to the magnet).
.
The invention comprises apparatus constructed on the same principle for
receiving electrical signals from a distance that is to say the coil or bobbin (or the
magnet) of the receiving instrument is carried by a spring and similarly vibrates
across the magnetic field when the spring is acted upon.
In connection with
receiving apparatus thus constructed the invention includes special arrangements
whereby the mechanism can be placed under or behind the bell. The invention
further comprises the combination of instruments constructed as above referred to
(that is to say instruments having coils or bobbins that are mounted on a spring
and made to vibrate in a magnetic field by the application of manual power
as described) with telephones or microphones. Also special arrangements of
commutators to be used in combination with instruments constructed as above
referred to.
According to one modification of transmitting apparatus the coil or bobbin is
situated between the poles of two horse-shoe magnets and is carried by the spring.

page_text: The bobbin is made with large polar expansions which at their end are bent at a
right angle with the object of utilising the largest portion of the magnetic field.
The bobbin has also two prolongations which come against stops and are intended
to prevent the spring becoming broken by over-beling. A handle or lever is
attached to the bobbin to enable the spring to be bent or moved to one side
together with the bobbin ; on releasing the handle after the spring has been thus
bent the spring and bobbin will vibrate between the magnetic poles.
According to another modification a magnet of circular section is bent into a
ring but so that its two poles are not in confact. Two coils or bobbins of insulated
wire put in tension with each other are placed upon or in proximity to the two
ends of the magnet respectively; these two coils are connected to each other by an
iron armature and this armature is connected by a spring with a spindle around
which it can vibrate. There is a fixed iron armature whose object is to concentrate
the magnetic field in the region of the coils and there is a handle or lever fixed to
one of the coils for the purpose of giving a vibrating motion to the movable part
of the apparatus. This being so, it is easy to understand that if the handle or
lever be displaced in the one direction or the other and then released the two coils
through the action of the spring receive a vibratory notion the result of which
will be to engender in the wire an undulatory electric current which will have a
tencion depending upon the diameter of the wire and the rapidity of the vibrations.
The currents engendered in the two coils are necessarily added together because at
cach pole of opposite sign the motions of the coils being of inverse direction the
direction of the current in each of the coils is always the same during the
continuance of a phase.
According to another modification the magnetic field is constituted by two
semi-circular magnets connected together so as to form two consequent poles.
There are two coils or bobbins connected by a stay or bar to the spindle around
which they can vibrate under the action of a spring. An iron piece and a handle
or lever act in this modification the same parts as in the preceding, but it should
be remarked 1st that in this case all the lines of force of the magnetic field are
entirely utilized for the production of the current, and that 2ndly the greatest
energy can be given to this by dividing the magnet into as many sectors as may
be desired and by adding a coil for every consequent pole thus formed.
According to another modification the magnetic field is as before constituted by
a magnet bent into a ring. Between the poles is placed a vibrating coil or bobbin
formed of a double T iron on the web or middle portion of which the wire is
wound; the spindle of the bobbin is held between supports and there are two
springs connecting the bobbin to a stay or cross-piece. A lever or handle fixed to
the bobbin allows of this being moved by hand upon its axis and this motion
having been effected the simultaneous action of the springs when the lever or
handle is freed will give to the coil a rapid vibrating motion. During the various
phases of this motion the electric current which arises in the induced wire and
which the binding screws allow of being collected will be of considerable energy
and capable of actuating at very great distances the receivers introduced into
the line.
Besides the action produced by the displacement of the wire in the magnetic
field, the vibratory motion of the iron core between the two poles will have for
result the development in the coil of a current, of an energy so much the greater,
as the reciprocal actions of iron on iron are the more powerful than those of copper
on iron. The arrangement of the different parts allows of the two currents thus
produced being added together in all cases.
It is not necessary to use springs in order to produce the oscillation of the
bobbin. By adding to its iron core a transverse piece the tendency of this piece to
preserve a given position will give to the whole of the movable part a vibratory
motion when it has been moved by the lever or handle from its position of
equilibrium.

page_text: For receiving electric signals. I employ apparatus based on the same principle as
the transmitting apparatus above described, all apparatus of this kind being
reversible. According to one modification of receiver a coil or bobbin with flat
core is mounted on a spring and placed between the poles of two magnets; the
other end of the bobbin carries the hammer of the bell of an electric alarum or
sounder.
In another modification the bobbin is fixed and it is only the soft iron core
which is movable between the magnetic poles. The core is carried by the spring
and itself carries the bell hammer.
In order to place all the mechanism of the electric bell or alarum under or
behind the bell I form the bells with an internal protuberance or boss upon which
the hammer strikes; or I have a movable iron core whose ends are bent square
and situated between the magnetic poles; this core is carried by two springs and
the knob of the hammer strikes normally upon the bell.
In order to effect the unlocking or release of discs or visual signals, I employ
a receiver constructed in a similar manner. A bobbin or coil is mounted on a
bracket the core of this coil is movable and is carried by a spring, as before; it
has a hammer which during the passage of the current strikes a hook or piece and
this in its turn unlocks or releases the disc or visual signal. By the succession of
blows the unlocking is ensured. The hooks receive a series of sufficiently powerful
blows to provent sticking which often occurs in apparatus of this kind.
The apparatus before described are applicable to telephonic purposes. It is easy
to arrange a telephonic or micro-telephonic station by making use of the same
magnets which constitute the call. This may be effected as follows:-In a box is
placed the call composed of a spring, of a vibrating bobbin or coil attached to tho
spring and of two magnets between the poles of which the bobbin is situated.
There is a lever or handle for moving the bobbin and its spring to cause the
vibrations as before described.
One of the magnets serves for polarizing the receiving electric bell or alarum
whose hammer strikes a protuberance or hoss on the interior of the bell. The
other magnet serves to polarize the coils of the telephone. Commutators connect
the circuits of this system so as to form a telephonic station.
The form and action of commutators used in apparatus for transmitting or
receiving signals can be changed according to requirements.
It is sometimes
necessary during repose for the transmitter to be separated from the circuit; this
result can be effected in the following manner-Under or behind the vibrating
spring which carries the movable bobbin is placed a piece which turns with
friction (or on springs) upon the frame of the apparatus.
In this piece near one end are fixed two pins or contacts which do not touch the
spring in the position of rest. The current passes through the spring and, when
the coil is vibrating, it passes into the external circuit through tho intermediation
of one or other of the pins. A contact can be added for the position of rest
which for telephonic installations allows of putting the electric bell in the circuit
and of separating it during the vibration of the coil.
Instead of the piece above described two small springs which bear respectively
against the two sides of the principal spring can be employed. In another modifi-
cation there is a rubber travelling without a commutator. A small brush is fixed
on the bobbin and it rubs during its travel upon the commutator which can be
arranged in various ways according to requirement.
Sometimes it is necessary to short circuit the coil when at rest from the
apparatus. This can easily be effected by similar methods to those above described.
When I employ for example two small springs respectively at the two sides of the
principal spring, I allow them to touch this spring, or a contact specially made,
and the current passes through the two springs without going through the coil.
During the vibrations of the coil and principal spring there is no direct contact
between the two small springs and the coil is introduced into the circuit. Thọ

page_text: result may be modified by fixing weights to the end of the small springs which by
their inertia will retard the closing of the contact. The same arrangement can be
adopted with rubbing or sliding contacts or by applying levers in lieu of the
springs:
In a modification particularly adapted for telephonic purposes the electric bell is
put in the circuit which goes direct through the two small springs and the coil of
the call in a circuit which goes through two other small springs similarly arranged
at the sides of the principal spring. This arrangement fulfils the office of an
ordinary telephonic call button.
According to another modification there are pivoted around the axis and on the
movable part of the call two balls which during the vibrations cause contacts
with two pieces on or connected with the vibrating spring and thus serve aš
commutators.

page_text: COMPLETE SPECIFICATION (AMENDED).
Improvements in Apparatus for Transmitting and Receiving
Electrical Signals.
I JOHN CLAYTON MEWBURN, of 109 Fleet Street in the City of London, Fellow
of the Institute of Patent Agents 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 has for its primary object the construction of apparatus of the kind
hereinafter described for transmitting electrical signals to a distance and consists in
means of producing the requisite current for this purpose by one or more coils or
bobbins which have a to and fro motion imparted to them in a magnetic field by means
of a spring or springs (or their equivalent) made to vibrate by being moved by the
application of manual power out of the norinal or central position and then released or
let go. The spring carries the coil (or it may carry the magnet instead of the coil)
and transforms the power applied into electricity by imparting the said to and fro or
vibrating motion to the coil (or to the magnet)."
The invention comprises apparatus constructed on the same principle for receiving
electrical signals from a distance that is to say, the coil or bobbin (or the magnet)
of the receiving instrument is carried by a spring and similarly vibrates across the
magnetic field when the spring is acted upon. In connection with receiving
apparatus thus constructed the invention includes special arrangements whereby
the mechanism can be placed under or behind the bell. The invention further.
comprises the combination of instruments constructed as above referred to (that is
to say, instruments having coils or bobbins that are mounted on n-spring and made
to vibrate in a magnetic field by the application of manual power as described)
with telephones or rierophones. Also special arrangements of commutators to be
used in combination with instruments constructed as above referred to:
According to one modification of transmitting apparatus which is represented in
Figure 1 of the drawings the coil or bobbin is situated between the poles of two
horse-shoe magnets N and S and is carried by the spring. The bobbin is made
with large polar expansions (as shown in the figures) which at their end are bent
at a right angle with the object of utilising the largest portion of the magnetic
field. The bobbin has also two prolongations a and which come against stops a¹
and and are intended to prevent the sping becoming broken by overbending,
A handle or lever is attached to the hobbin to enable the spring to be bent or
moved to one side together with the bobbin on releasing the handle after the
spring has been thus bent the spring and bobbin will vibrate between the magnetic
poles.
According to another modification which is represented in Figure 8 a magnet A
of circular section is bent into a ring but so that its two poles N and S are not in
contact. Two coils or hobbins B, B of insulated wire put in tension with each
other are placed upon or in proximity to the two ends of the magnet respectively;
these two coils which in the normal state occupy in relation to the magnet the
position indicated in the drawing are connected to each other by an iron armature D
and this armature is connected by a spring with a spindle O around which it can

page_text: vibrate. Cis a fixed iron armature whose object is to concentrate the magnetic
field in the region of the coils B, B' and L is a handle or lever fixed to the coil B
for the purpose of giving a vibrating motion to the movable part of the apparatus.
This being so it is easy to understand that if the handle or lever L he displaced in
the one direction or the other and then released the two coils through the action of
the spring will receive a vibratory motion the result of which will be to engender
in the wire an undulatory electric current which will have a tension depending
upon the diameter of the wire and the rapidity of the vibrations. The currents
engendered in the two coils are necessarily added together because at each pole of
opposite sign the motions of the coils being of inverse direction the direction of
the current in each of the coils is always the same during the continuance of a
phase.
According to another modfiication represented in Figure 9 the magnetic field is
constituted by two semi-circular magnets connected together so as to form two
consequent poles N and S. B, B are two coils or bobbins connected by a stay or
bar to the spindle around which they can vibrate under the action of a spring r
An iron piece C and a handle or lever Lact in this modification the same parts as
in the preceding but it should be remarked, 1st that in this case all the lines of
force of the magnetic field are entirely utilized for the production of the current,
and that 2ndly the greatest energy can be given to this by dividing the magnet
into as many sectors as may be desired and by adding a coil for every consequent
pole thus formed.
According to another modification represented in Figures 10 and 11 the magnetic
field is as before constituted by a magnet A bent into a ring. Between the poles N
and S is placed a vibrating coil or bobbin formed of a double T iron on the web
or middle portion of which the wire is wound; the spindle 0 of the bobbin is
held between supports C, and there are two springs, connecting the bobbin
to a stay or cross piece D. A lover or handle L fixed to the bobbin allows of this
being moved by hand upon its axis and this motion having been effected the
simultaneous action of the springs, when the lever or handle is freed will give
to the coil a rapid vibrating motion. During the various phases of this motion the
electric current which arises in the induced wire and which the binding screws b, b
allow of being collected will be of considerable energy and capable of actuating at
very great distances the receivers introduced into the line. Besides the action
produced by the displacement of the wire in the magnetic field the vibratory
motion of the iron core B between the two poles will have for result the develop-
ment in the coil of a current of an energy so much the greater as the reciprocal
actions of iron on iron are the more powerful than those of copper on iron. The
arrangement of the different parts allows of the two currents thus produced being
added together in all cases.
It is not necessary to use springs in order to produce the vibration of the bobbin.
By arranging the apparatus as shown in Figure 12 that is to say, by adding to its
iron core B a transverse piece E the tendency of this piece to preserve the position
which it occupies in the figure will give to the whole of the movable part a
vibratory motion when it has been moved by the lever or handle from its position
of equilibrium.
For receiving electric signals I employ apparatus based on the same principle as
the transmitting apparatus above described, all apparatus of this kind being
reversible. According to one modification of receiver, which is represented in
Figure 2, a coil or bobbin B with flat core is mounted on a spring R and placed
between the poles of two magnets N and S; the end of the bobbin carries the
hammer of the hell of an electric alarum or sounder. In another modification
shown in Figure 3 the bobbin B is fixed and it is only the soft iron core which
is movable between the magnetic poles N and S. The core is carried by the
spring R and iself carries the bell hammer.
In order to place all the mechanism of the electric bell or alarum under or
behind the bell I form the bells with an internal protuberance or boss (see P,

page_text: :
Figure 4) upon which the hammer strikes or I have a movable iron core F, F
Figure 5, whose ends are bent square and situated between the magnetic poles N, S:
this core is carried by two springs R, R¹ and the knob of the hammer strikes
normally upon the bell.
In order to effect the unlocking or release of dises or visual signals, I employ a
receiver constructed in a similar manner. A bobbin or coil B (see Figure 6) is
mounted on a bracket K; the core F of this bobbin is movable and is carried by
a spring Ras before; it has a hammer which during the passage of the current
strikes a hook or piece C and this in its turn unlocks or releases the disc or visual
signal D. By the succession of blows the unlocking is ensured. The hooks receive
a series of sufficiently powerful blows to prevent sticking which often occurs in
apparatus of this kind.
It is easy
The apparatus before described are applicable to telephonie purposes.
to arrange a telephonic or micro telephonic station by making use of the same
magnets which constitute the call. This may be effected as shown in Figure 7.
In a box F, F is placed the call composed of a spring R, of a vibrating hobbin or
coil B attached to the spring and of two magnets N, S between the poles of which
the bobbin is situated. There is a lever or handle for moving the bobbin and its
spring to cause the vibrations as before described. One of the magnets serves
for polarizing the receiving electric bell or alarum B whose hamuner strikes a
protuberance or boss P on the interior of the bell. The other magnet serves to
polarize the coils K, K' of the telephone. Commutators connect the circuits of this
system so as to form a telephonic station.
The form and action of commutators used in apparatus for transmitting or
receiving signals can be changed according to requirements. It is sometimes
necessary during repose for the transmitter to be separated from the circuit; this
result can be effected in the following manner. Under or behind the vibrating
spring see R. Figure 13-which carries the movable bobbin is placed a piece A, B
which turns with friction (or on springs) upon the frame of the apparatus. In this
piece near the end B are fixed two pins or contacts a and which do not touch
the spring in the position of rest. The current passes through the spring and when
the bobbin is vibrating it passes into the external circuit through the inter-
mediation of one or other of the pins. A contact can be added for the position of
rest which for telephonic installations allows of putting the electric bell in the
circuit and of separating it during the vibration of the bobbin. Instead of the
piece A B two small springs r, (see Figure 14) which bear respectively against
the two sides of the principal spring R can be employed. In another modification
there is a rubber travelling without a commutator. A small brush is fixed on the
bobbin and it rubs during its travel upon the commutator which can be arranged
in various ways according to requirement.
Sometimes it is necessary to short circuit the bobbin when at rest from the
apparatus. This can easily be effected by similar methods to those above described.
When I employ, for example, two small springs respectively at the two sides of the
principal spring seer, Figure 15, I allow them to touch this spring, or a contact
specially made and the current passes through the two springs from A to B without
going through the bobbin. During the vibrations of the bobbin and principal
spring there is no direct contact between the two small springs, and the
bobbin is introduced into the circuit. The result may be modified by fixing
weights to the end of the small springs and which by their inertia will retar
the closing of the contact. The same arrangement can be adopted with rubbing
or sliding contacts or by applying levers in lieu of, the springs.
In a modification represented in Figure 16 and particularly adapted for telephonic
purposes the electric bell is put in the circuit which goes direct through the two
small springs from A to B and the bobbin of the call is put in a circuit which goes
from Cto through two other small springs similarly arranged at the sides of the
principal spring. This arrangement fulfils the office of an ordinary telephonic call
button which is represented in Figure 17. The line current enters the spring R

page_text: which in its position of repose bears on the contact F of the bell; when the button B
is pressed the contact. F is broken and contact is made at F' with the call.
According to another modification, which is represented in Figure 18 there are
pivoted around the axis and on the movable part of the call two balls B and B'
which during the vibrations cause contacts with two pieces and a on or connected
with the vibrating spring and thus serve as commutators.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, as communicated
to me,
I declare that I do not claim generally the use of a coil and magnet used in
combination to generate currents of electricity by causing one or the other when mounted on
a spring to vibrate by the application of manual power as such is described in the
Specification of Letters Patent granted to Charles Denton Abel on behalf of Bruno
Abdank Abakanowicz and dated 17th April 1883 No. 1952 nor do I claim what is
contained in the specification of Letters Patent of Charles William Siemens of
25th June 1872 No. 1919 but what I claim in respect of apparatus for transmitting
and receiving electrical signals is :-
:-
1. Constructing apparatus substantially as herein before described with referenco
to the annexed drawings figures for transmitting electrical signals to a distance.
2. The employment in transmitting apparatus of bobbins or coils of special
form with very large polar expansions as hereinbefore described with reference to
Figure 1.
3. Constructing such bobbins with projections of the form indicated in Figure 1
to serve no stop.
3. The arrangements hereinbefore described with reference respectively to
Figures 8 and 9.
4. Constructing apparatus for receiving electrical signals with a hobbin mounted
on a spring and vibrating across the magnetic field substantially as hereinbefore
described and represented in Figure 2.
6.5. The modified arrangement in which the bobbin is fixed and only the core
movable substantially as hereinbefore described and represented in Figure 3.
7. The employment of bells having an abutment or boss on which the hummer
strikes-substantially as hereinbefore described with reference to Figure 4.
6. The arrangement substantially as herein before described with reference to
Figure 5 in which there is a fixed bobbin with movable iron core mounted on two
springs.
7. The arrangement of receivers constructed as described as visual signals by
applying a vibrating hammer as represented in Figure 6 which strikes repeated
blows on the unlocking or releasing apparatus.
10. The combination of the calls hereinbefore described with telephones or
microphones by utilising the magnets of these calls substantially us hereinbefore
described with reference to Figure: to polarize the necessary parts.
11. The application as set forth of automatic commutators to the magnetie
signals to allow of separating the bobbin or coil (generator of the current) from the
eirenit or of chort circuiting it substantially as hereinbefore described with reference
to Figures 13, 14 and 15,
12. The application to the same apparatus as set forth of commutators which
besides the functions above stated still give u contact at the time of repose,
an application which can be utiliced for special requirements us, for instance,
for tele; honie-purposes, substantially us hereinbefore--described with reference to
Figures 16, 17 und 18.

page_text: I JOHN CLAYTON MEWBURN of 169 Fleet Street, in the City of London, Fellow
of the Institute of Patents Agents do hereby declare the nature of my invention
for "IMPROVEMENTS IN APPARATUS FOR TRANSMITTING AND RECEIVING ELECTRICAL
SIGNALS to be as follows:-
"
:-
This invention has for its primary object the construction of apparatus for
transmitting electrical signals to a distance, and consists in means of producing the
requisite current for this purpose by one or more coils or bobbins which have a to
and fro motion imparted to them in a magnetic field by means of a spring or
springs or their equivalent made to vibrate by being moved by the application of
manual power out of the normal or central position and then released or let go.
The spring carries the coil (or it may carry the magnet instead of the coil) and
transforms the power applied into electricity by imparting the said to and fro or
vibrating motion to the coil (or to the magnet).
The invention comprises apparatus constructed on the same principle for
receiving electrical signals from a distance that is to say the coil or. bobbin (or the
magnet) of the receiving instrument is carried by a spring and similarly vibrates
across the magnetic field when the spring is acted upon. In connection with
receiving apparatus thus constructed the invention includes special arrangements
whereby the mechanism can be placed under or behind the bell. The invention
further comprises the combination of instruments constructed as above referred to
(that is to say instruments having coils or bobbins that are mounted on a spring
and made to vibrate in a magnetic field by the application of manual power
as described) with telephones or microphones. Also special arrangements of
commutators to be used in combination with instruments constructed as above
referred to.
According to one modification of transmitting apparatus the coil or bobbin is
situated between the poles of two horse-shoe magnets and is carried by the spring.

page_text: The bobbin is made with large polar expansions which at their end are bent at a
right angle with the object of utilising the largest portion of the magnetic field.
The bobbin has also two prolongations which come against stops and are intended
to prevent the spring becoming broken by over-bending. A handle or lever is
attached to the bobbin to enable the spring to be bent or moved to one. side
together with the bobbin; on releasing the handle after the spring has been thus
bent the spring and bobbin will vibrate between the magnetic poles.
According to another modification a magnet of circular section is bent into a
ring but so that its two poles are not in contact. Two coils or bobbins of insulated
wire put, in tension with each other are placed upon or in proximity to the two
ends of the magnet respectively; these two coils are connected to each other by an
iron armature and this armature is connected by a spring with a spindle around
which it can vibrate. There is a fixed iron armature whose object is to concentrate
the magnetic field in the region of the coils and there is a handle or lever fixed to
one of the coils for the purpose of giving a vibrating motion to the movable part
of the apparatus. This being so, it is easy to understand that if the handle or
lever be displaced in the one direction or the other and then released the two coils
through the action of the spring receive a vibratory motion the result of which
will be to engender in the wire an undulatory electric current which will have n
tension depending upon the diameter of the wire and the rapidity of the vibrations.
The currents engendered in the two coils are necessarily added together because at
each pole of opposite sign the motions of the coils being of inverse direction the
direction of the current in each of the coils is always the same during the
continuance of a phase.
According to another modification the magnetic field is constituted by two
semi-circular maguets connected together so as to form two consequent poles.
There are two coils or bobbins connected by a stay or bar to the spindle around
which they can vibrate under the action of a spring. An iron piece and a handle
or lever act in this modification the same parts as in the preceding, but it should
be remarked 1st that in this case all the lines of force of the magnetic field are
entirely utilized for the production of the current, and that 2ndly the greatest
energy can be given to this by dividing the magnet into as many sectors as may
be desired and by adding a coil for every consequent pole thus formed.
According to another modification the magnetic field is as before constituted by
a magnet bent into a ring. Between the poles is placed a vibrating coil or bobbin
formed of a double T iron on the web or middle portion of which the wire is
wound; the spindle of the bobbin is held between supports and there are two
springs connecting the bobbin to a stay or cross-piece. A lever or handle fixed to
the bobbin allows of this being moved by hand upon its axis and this motion
having been effected the simultaneous action of the springs when the lever or
handle is freed will give to the coil a rapid vibrating motion. During the various
phases of this motion the electric current which arises in the induced wire and
which the binding screws allow of being collected will be of considerable energy
and capable of actuating at very great distances the receivers introduced into
the line.
Besides the action produced by the displacement of the wire in the magnetic
field, the vibratory motion of the iron core between the two poles will have for
result the development in the coil of a current, of an energy so much the greater,
as the reciprocal actions of iron on iron are the more powerful than those of copper
on iron. The arrangement of the different parts allows of the two currents thus
produced being added together in all cases.
It is not necessary to use springs in order to produce the oscillation of the
bobbin. By adding to its iron core a transverse piece the tendency of this piece to
preserve a given position will give to the whole of the movable part a vibratory
motion when it has been moved by the lever or handle from its position of
equilibrium. -

page_text: For receiving electric signals I employ apparatus based on the saine principle as
the transmitting apparatus above described, all apparatus of this kind being
reversible. According to one modification of receiver a coil or bobbin with flat
core is mounted on a spring and placed between the poles of two magnets; the
other end of the bobbin carries the hammer of the bell of an electric alarum or
sounder.
In another modification the bobbin is fixed and it is only the soft iron core
which is movable between the magnetic poles. The core is carried by the spring
and itself carries the bell hammer.
In order to place all the mechanism of the electric bell or alarum under or
behind the bell I form the bells with an internal protuberance or boss upon which
the hammer strikes; or I have a movable iron core whose ends are bent square
and situated between the magnetic poles; this core is carried by two springs and
the knob of the hammer strikes normally upon the bell.
In order to effect the unlocking or release of discs or visual signals, I employ
a receiver constructed in a similar manner. A bobbin or coil is mounted on a
bracket; the core of this coil is movable and is carried by a spring, as before; it
has a hammer which during the passage of the current strikes a hook or piece and
this in its turn unlocks or releases the disc or visual signal. By the succession of
blows the unlocking is ensured. The hooks receive a series of sufficiently powerful
blows to prevent sticking which often occurs in apparatus of this kind.
The apparatus before described are applicable to telephonic purposes. It is easy
to arrange a telephonic or micro-telephonic station by making use of the same
magnets which constitute the call. This may be effected as follows:-In a box is
placed the call composed of a spring, of a vibrating bobbin or coil attached to the
spring and of two magnets between the poles of which the bobbin is situated.
There is a lever or handle for moving the bobbin and its spring to cause the
vibrations as before described.
One of the magnets serves for polarizing the receiving electric bell or alarum
whose hammer strikes a protuberance or boss on the interior of the bell. The
other magnet serves to polarize the coils of the telephone. Commutators connect
the circuits of this system so as to form a telephonic station.
The form and action of commutators used in apparatus for transmitting or
receiving signals can be changed according to requirements. It is sometimes
necessary during repose for the transmitter to be separated from the circuit; this
result can be effected in the following manner:-Under or behind the vibrating
spring which carries the inovable bobbin is placed a piece, which turns with
friction (or on springs) upon the frame of the apparatus.
In this piece near one end are fixed two pius or contacts which do not touch the
spring in the position of rest. The current passes through the spring and, when
the coil is vibrating, it passes into the external circuit through the intermediation
of one or other of the pins. A contact can be added for the position of rest
which for telephonic installations allows of putting the electric bell in the circuit
and of separating it during the vibration of the coil.
Instead of the piece above described two small springs which bear respectively
against the two sides of the principal spring can be employed. In another mediti-
cation there is a rubber travelling without a commutator. A small brush is fixed
on the bobbin and it rubs during its travel upon the commutator which can be
arranged in various ways according to requirement.
Sometimes it is necessary to short circuit the coil when at rest from the
apparatus. This can easily be effected by similar methods to those above described.
When I employ for example two small springs respectively at the two sides of the
principal spring, I allow them to touch this spring, or a contact specially made,
and the current passes through the two springs without going through the coil.
During the vibrations of the coil and principal spring there is no direct contact
between the two small springs and the coil is introduced into the circuit. The

page_text: result may be modified by fixing weights to the end of the small springs which by
their inertia will retard the closing of the contact. The same arrangement can be
adopted with rubbing or sliding contacts or by applying levers in lieu of the
springs..
In a modification particularly adapted for telephonic purposes the electric bell is
put in the circuit which goes direct through the two small springs and the coil of
the call in a circuit which goes through two other small springs similarly arranged
at the sides of the principal spring. This arrangement fulfils the office of an
ordinary telephonic call button.
According to another modification there are pivoted around the axis and on the
movable part of the call two balls which during the vibrations cause contacts
with two pieces on or connected with the vibrating spring and thus "serve as
commutators.

page_text: Improvements in Apparatus for Transmitting and Receiving
Electrical Signals.
I JOHN CLAYTON MEWBURN, of 109 Fleet Street in the City of London, Fellow
of the Institute of Patent Agents 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 has for its primary object the construction of apparatus for
transmitting electrical signals to a distance and consists in means of producing the
requisite current for this purpose by one or more coils or bobbins which have a to
and fro motion imparted to them in a magnetic field by means of a spring or
springs (or their equivalent) made to vibrate by being moved by the application
of manual power out of the normal or central position and then released or let go.
The spring carries the coil (or it may carry the magnet instead of the coil) and
transforms the power applied into electricity by imparting the said to and fro or
vibrating motion to the coil (or to the magnet).
The invention comprises apparatus constructed on the same principle for receiving
electrical signals from a distance that is to say, the coil or bobbin (or the magnet)
of the receiving instrument is carried by a spring and similarly vibrates across the
magnetic field when the spring is acted upon. In connection with receiving
apparatus thus constructed the invention includes special arrangements whereby
the mechanism can be placed under or behind the bell. The invention further
comprises the combination of instruments constructed as above referred to (that is
to say, instruments having coils or bobbins that are mounted on a spring and made
to vibrate in a magnetic field by the application of manual power as described)
with telephones or microphones. Also special arrangements of commutators to be
used in combination with instruments constructed as above referred to.
According to one modification of transmitting apparatus which is represented in
Figure 1 of the drawings the coil or bobbin is situated between the poles of two
horse-shoe maguets N and S and is carried by the spring. The bobbin is made
with large polar expansions (as shown in the figures) which at their end are bent
at a right angle with the object of utilising the largest portion of the magnetic
field. The bobbin has also two prolongations a and b which come against stops a'
and b' and are intended to prevent the spring becoming broken by overbending.
A handle or lever is attached to the bobbin to enable the spring to be bent or
moved to one side together with the bobbin; on releasing the handle after the
spring has been thus bent the spring and bobbin will vibrate between the magnetic
poles.
According to another modification which is represented in Figure 8 a magnet A
of circular section is bent into a ring but so that its two poles N and S are not in
contact. Two coils or bobbins B, B₁ of insulated wire put in tension with each
other are placed upon or in proximity to the two ends of the magnet respectively;
these two coils which in the normal state occupy in relation to the magnet the
position indicated in the drawing are connected to each other by an iron armature D
and this armature is connected by a spring with a spindle O around which it can

page_text: vibrate. C is a fixed iron armature whose object is to concentrate the magnetic
field in the region of the coils B, B and L is a handle or lever fixed to the coil B¹
for the purpose of giving a vibrating motion to the movable part of the apparatus.
This being so it is easy to understand that if the handle or lever L be displaced in
the one direction or the other and then released the two coils through the action of
the spring will receive a vibratory motion the result of which will be to engender
in the wire an undulatory electric current which will have a tension depending
upon the diameter of the wire and the rapidity of the vibrations. The currents
engendered in the two coils are necessarily added together because at each pole of
opposite sign the motions of the coils being of inverse direction the direction of
the current in each of the coils is always the same during the continuance of a.
phase.
According to another modification represented in Figure 9 the magnetic field is
constituted by two semi-circular magnets connected together so as to form two
consequent poles N and S. B, B' are two coils or bobbins connected by a stay or
bar d to the spindle O around which they can vibrate under the action of a spring r.
An iron piece C and a handle or lever L act in this modification the same parts as
in the preceding but it should be remarked, 1st that in this case all the lines of
force of the magnetic field aro entirely utilized for the production of the current,
and that 2ndly the greatest energy can be given to this by dividing the magnet
into as many sectors as may be desired and by adding a coil for every consequent
pole thus formed.
+
According to another modification represented in Figures 10 and 11 the magnetic
field is as before constituted by a magnet A bent into a ring. Between the poles N
and S is placed a vibrating coil or bobbin formed of a double T iron on the web
or middle portion of which the wire is wound; the spindle O of the bobbin is
held between supports C, C' and there are two springs r, connecting the bobbin
to a stay or cross piece D. A lever or handle L fixed to the bobbin allows of this
being moved by hand upon its axis and this motion having been effected the
simultaneous action of the springs, when the lever or handle is freed will give
to the coil a rapid vibrating motion. During the various phases of this motion the
electric current which arises in the induced wire and which the binding screws b, b
allow of being collected will be of considerable energy and capable of actuating at
very great distances the receivers introduced into the line." Besides the action
produced by the displacement of the wire in the magnetic field the vibratory
notion of the iron core B between the two poles will have for result the develop-
ment in the coil of a current of an energy so much the greater as the reciprocal
actions of iron on iron are the more powerful than those of copper on iron. The
arrangement of the different parts allows of the two currents thus produced being
added together in all cases.
It is not necessary to use springs in order to produce the vibration of the bobbin.
By arranging the apparatus as shewn in Figure 12 that is to say, by adding to its
iron core B a transverse piece. E the tendency of this piece to preserve the position
which it occupies in the figure will give to the whole of the movable part a
vibratory motion when it has been moved by the lever or handle from its position
of equilibrium.
For receiving electric signals I employ apparatus based on the same principle as
the transmitting apparatus above described, all apparatus of this kind being
reversible. According to one modification of receiver, which is represented in
Figure 2, a coil or bobbin B with flat core is mounted on a spring R and placed
between the poles of two magnets N and S; the end of the bobbin carries the
hammer b of the bell of an electric alarum or sounder. In another modification
shown in Figure 3 the bobbin B is fixed and it is only the soft iron core F which
is movable between the magnetic poles N and S. The core is carried by the
Spring R and itself carries the bell hammer.
In order to place all the mechanism of the electric bell or alarum under or
behind the bell I form the bells with an internal protuberance or boss (see P,

page_text: Figure 4) upon which the hammer strikes; or I have a movable iron core F, F
Figure 5, whose ends are bent square and situated between the magnetic poles N, S;
this core is carried by two springs R, R¹ and the knob of the hammer strikes
normally upon the bell.
In order to effect the unlocking or release of discs or visual signals, I employ a
receiver constructed in a similar manner. A bobbin or coil B (see Figure 6) is
mounted on a bracket K; the core F of this bobbin is movable and is carried by
a spring R as before; it has a hammer b which during the passage of the current
strikes a hook or piece C and this in its turn unlocks or releases the disc or visual
signal D. By the succession of blows the unlocking is ensured. The hooks receive
a series of sufficiently powerful blows to prevent sticking which often occurs in
apparatus of this kind.
The apparatus before described are applicable to telephonic purposes. It is easy
to arrange a telephonic or micro telephonic station by making use of the same
magnets which constitute the call. This may be effected as shown in Figure 7.
In a box F, F is placed the call composed of a spring R, of a vibrating bobbin or
coil B attached to the spring and of two magnets N, S between the poles of which
the bobbin is situated. There is a lever or handle for moving the bobbin and its
spring to cause the vibrations as before described. One of the magnets serves
for polarizing the receiving electric bell or alarum B' whose hammer strikes a
protuberance or boss P on the interior of the bell. The other magnet serves to
polarize the coils K, K¹ of the telephone. Commutators connect the circuits of this
system so as to form a telephonic station.
The form and action of commutators used in apparatus for transmitting or
receiving signals can be changed according to requirements. It is sometimes
necessary during repose for the transmitter to be separated from the circuit; this
result can be effected in the following manner. Under or behind the vibrating
spring-see R, Figure 13-which carries the movable bobbin is placed a piece A, B
which turns with friction (or on springs) upon the frame of the apparatus. In this
piece near the end B are fixed two pins or contacts a and b which do not touch
the spring in the position of rest. The current passes through the spring and when
the bobbin is vibrating it passes into the external circuit through the inter-
mediation of one or other of the pins. A contact can be added for the position of
reat which for telephonic installations allows of putting the electric bell in the
circuit and of separating it during the vibration of the bobbin. Instead of the
piece A B two small springs », r (see Figure 14) which bear respectively against
the two sides of the principal spring R can be employed. In another modification
there is a rubber travelling without a commutator. A small brush is fixed on the
bobbin and it rubs during its travel upon the commutator which can be arranged
in various ways according to requirement.
Sometimes it is necessary to short circuit the bobbin when at rest from the
apparatus. This can easily be effected by similar methods to those above described.
When I employ, for example, two small springs respectively at the two sides of the
principal spring see r, r¹ Figure 15, I allow them to touch this spring, or a contact
specially made and the current passes through the two springs from A to B without
going through the bobbin. During the vibrations of the bobbin and principal
spring there is no direct contact between the two small springs r, and the
bobbin is introduced into the circuit. The result may be modified by fixing
weights to the end of the small springs and ¹ which by their inertia will retard
the closing of the contact. The same arrangement can be adopted with rubbing
or sliding contacts or by applying levers in lieu of, the springs.
In a modification represented in Figure 16 and particularly adapted for telephonic
purposes the electric bell is put in the circuit which goes direct through the two
small springs from A to B and the bobbin of the call is put in a circuit which goes
from C to D through two other small springs similarly arranged at the sides of the
principal spring. This arrangement fulfils the office of an ordinary telephonic call
button which is represented in Figure 17. The line current enters the spring R

page_text: which in its position of repose bears on the contact F of the bell; when the
button B is pressed the contact F is broken and contact is made at F1 with
the call.
According to another modification, which is represented in Figure 18 there are
pivoted around the axis and on the movable part of the call two balls Band B'
which during the vibrations cause contacts with two pieces band a on or connected
with the vibrating spring and thus serve as commutators.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, as communicated
to me, I declare that what I claim in respect of apparatus for transmitting and
receiving electrical signals is
1. Constructing apparatus substantially as hercin before described with reference
to the annexed drawings for transmitting electrical signals to a distance.
2. The employment in transmitting apparatus of bobbins or coils of special
form with very large polar expansions as hereinbefore described with reference to
Figure 1.
3. Constructing such bobbins with projections of the form indicated in Figure 1
to serve as stops.
4. The arrangements hercinbefore described with reference respectively to
Figures 8 and 9.
5. Constructing apparatus for receiving electrical signals with a bobbin mounted
on a spring and vibrating across the magnetic field substantially as hereinbefore
described and represented in Figure 2.
6. The modified arrangement in which the bobbin is fixed and only the core
movable substantially as hereinbefore described and represented in Figure 3.
7. The employment of bells having an abutment or boss on which the hammer
strikes substantially as hereinbefore described with reference to Figure 4.
8. The arrangement substantially as hereinbefore described with reference to
Figure 5 in which there is a fixed bobbin with movable iron core mounted on two
springs.
9. The arrangement of receivers constructed as described as visual signals by
applying a vibrating hammer as represented in Figure 6 which strikes repeated
blows on the unlocking or releasing apparatus.
10. The combination of the calls herein before described with telephones or
microphones by utilising the magnets of these calls substantially as hereinbefore
described with reference to Figure 7-to polarize the necessary parts.
11. The application as set forth of automatic commutators to the magnetic
signals to allow of separating the bobbin or coil (generator of the current) from the
circuit or of short circuiting it substantially as hereinbefore described with reference
to Figures 13, 14 and 15.
12. The application to the same apparatus as set forth of commutators which
besides the functions above stated still give a contact at the time of repose,
an application which can be utilized for special requirements as, for instance,
for telephonic purposes, substantially as hereinbefore described with reference to
Figures 16, 17 and 18.