IMPROVE- MENTS IN TELEGRAPHIC TRANSMITTING INSTRUMENTS to be as follows:
Year: 1884

page_text: I FREDERICK HERBERT WILLIAM HIGGINS of 17 Cornhill in the City of London,
Electrical Engineer do hereby declare the nature of said invention for "IMPROVE-
MENTS IN TELEGRAPHIC TRANSMITTING INSTRUMENTS to be as follows:-
"
This invention has for its object improvements in telegraphic transmitting
instruments and relates to the class of transmitting instruments in which a barrel
with pins upon it is stopped by depressing finger keys corresponding to the letters
of the alphabet and other symbols and in which the pin barrel when permitted
to revolve carries round with it a wheel with projections and spaces which as
it revolves produces a succession of contacts causing currents to be transmitted
through the line wire.
In such a transmitting instrument I provide in connection with this contact
making wheel two separate contact springs each in a separate local battery circuit
including a relay. The wheel in revolving closes these circuits alternately and the
relays transmit currents the one positive currents and the other negative into the
line. This arrangement obviates any tendency to vibration of the contact springs
on the face of the contact making wheel and also simplifies the apparatus.
Between the relays and the line wire I provide a connection with a condensor by
which I prevent sparking at the relay contacts and strengthen the signals.
The pin barrel when released by the finger keys is carried forward by a pawl
dropping into teeth in a wheel driven by an electro-motor.
To obtain a smooth action in starting I interpose a spring connection between
the pawl and the pin barrel; when this precaution is not taken there is a risk of
the first current of a series not being efficiently transmitted when working at high
speeds.
Dated this 0th day of September 188A

page_text: "
I FREDERICK HERBERT WILLIAM HIGGINS of 17 Cornhill in the City of London
Electrical Engineer do hereby declare the nature of my invention for "IMPROVE-
MENTS IN TELEGRAPHIC TRANSMITTING INSTRUMENTS 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 object improvements in telegraphic transmitting
instruments and relates to the class of transmitting instruments in which a barrel
with pins upon it is stopped by depressing finger keys corresponding to the letters
of the alphabet and other symbols and in which the pin barrel when permitted to
revolve carries round with it a wheel with projections and spaces which as it
revolves produces a succession of contacts.
provide the key transmitter with two separate contact springs making contact
alternately upon the contact wheel.
Each contact spring has its separate circuit.
In one of these circuits are relays for transmitting positive impulses or currents
along a series of telegraphic lines.
In the other circuit are other relays for transmitting negative impulses or
currents along these lines.
Condensors are applied to avoid sparking at the contacts and to strengthen the
signals.
The pin barrel is connected with the contact wheel by a spring. There is also
a pawl which dropping into teeth in a wheel carries the contact wheel and barrel
forwards by connecting them positively with the motor.
On stopping the pin barrel the spring becomes distended and the pawl is lifted.
On the release of the pin barrel the spring reacts and replaces the pawl in gear.
Figure 1 is a plan and Figure 2 is an elevation of a portion of the key apparatus
of the transmitter.
A is a ratchet wheel which is driven continuously by an electric or other motor.
The side of this wheel is recessed and it receives into it a disc B which is fast upon
the axis C. Between the faces of the wheel A and the disc B a piece of cloth
saturated with oil is introduced and the axis C is pressed forward by a spring so as
to keep these surfaces always in contact. Hence the ratchet wheel A in revolving
tends constantly to carry the disc B and the axis C round with it by friction
independently of the intermittent positive connection which I will presently more
fully describe.
D is the contact wheel, it is fast with the disc A.
EE are the contact springs which coming in contact with projections on the
wheel D close the electric circuit as hereinafter described.
*E* Ex are abutments on to which the springs E'. E². fall when they leave the
projections on the wheel D.
Fis the pin barrel and F' are pins spirally arranged around it and corresponding
each to one of the letters signs or symbols to be transmitted. The barrel Fis loose
upon the axis C but except when a finger key is depressed is carried around with
it. It is provided with an arm F and this by a spring G is connected with a stud
projecting from the side of the contact wheel D. A pin upon the arm F2 projects
through a slotted hole in the wheel D and on the further side of the wheel is
connected by a link H with one extremity of a pawl lever K.
The pawl lever K is pivoted upon a bracket L which in turn is jointed upon the
hinder face of the wheel D. A spring L¹ keeps this bracket Lagainst a stop D* on

page_text: the wheel D so that under all conditions of proper working the bracket L is as if
rigidly fixed to the wheel D.
When the pawl K engages with the teeth of the ratchet wheel A (which is the
normal position whilst running) the pin barrel F is carried round with the motor
by a direct connection but a disconnection is effected by the operation of the finger
keys as follows:-
M M are the finger keys; when one of them is put down it raises the corre-
sponding projection N which is carried by a blade spring N' the projection N is
thus placed in the track of one of the pins F and when this pin comes round it
strikes upon the projection and the barrel F is stopped. The wheel D for a moment
however continues to revolve; this carries the stud on the arm F' from one end to
the other of the slot in the wheel D distending the spring G and causing the link H
to pull upon the end of the pawl lever K to which it is attached and thereby the
other end of the pawl lever is lifted out of gear with the ratchet teeth. The
contact wheel D and also the axis C with the disc B then all remain stationary
although the ratchet wheel A always revolves with the motor.
When the finger key is released the pin barrel F is immediately started into
motion by the action of the spring G. The disc B and the wheel D and axis O
being now free also start in consequence of the friction upon the surface of
the disc B.
In consequence of the more rapid movement of the barrel F resulting from the
action of the spring G the pawl K drops into gear with the teeth of the ratchet
wheel A and then the barrel F becomes positively driven as at the commencement.
These arrangements tend to prevent shock in stopping and starting-the pin
barrel F and the wheel D not being fast together are stopped separately with loss
jar than would result from stopping them simultaneously.
Also in starting the wheel D is gradually started by friction during the time that
the spring G takes to cause the pin barrel to overtake the wheel and not till then
does the pawl drop in and positively connect the wheel with the motor. Both the
friction between A and B and the tension of the spring G are capable of adjustment.
If the pawl were to drop into gear whilst the wheel was at rest the jar might
produce a tremor causing an imperfoct contact on the projection first passing
beneath the contact spring finger.
The use of two springs E and E³ to close the circuit alternately and these
operating with a wheel having half as many projections as there are contacts
required during a revolution also tends to give great steadiness to the contacts in
rapid running as each spring is allowed a period of rest after falling from the
projection. The firm abutments Ex on to which the springs fall also tend to check
their vibrations.
The system of working with separate contact springs closing the local circuit
alternately (whilst the contact wheel revolves) through one or other of two sets of
simple relays (as hereinafter more fully described) is also very convenient.
Figure 3 is a diagram showing the whole set of transmitting instruments and the
way in which the key transmitter is coupled with the others in conjunction with
which it operates.
In this diagram O represents the electric motor by which the ratchet wheel A is
to be continuously driven. O¹ is the battery from which the power is derived. O*
is a galvanometer in the circuit indicating the strength of the battery current.
Os is a key for opening the circuit of the motor battery to stop the motor when
it is not required for use.
D as before is the contact wheel and E¹ and E² the contact springs coming
alternately in contact with projections upon the wheel.
The point C indicates diagrametrically the axis of the wheel D or a spring bearing
constantly upon the axis and always in electrical connection with the axis and
with the wheel D. P is a local battery its circuit is closed whenever either of the
springs E¹ or E' is in contact with the wheel D whilst at other times it is open.

page_text: QQ are condensers and R¹ R2 R³ are relays through the coils of which the current
from the battery P passes when the circuit is closed. There is one set of relays R'
R2 R3 in connection with each telegraphic line to which these telegraph transmitting
instruments are employed to transmit. In the diagram two telegraph lines are
indicated and consequently there are two vertical rows of relays R¹ R² R³ but in
practice the number of lines and hence rows of relays will often be very numerous.
The condensers QQ are applied as shunts to these relays to receive the discharge
from their coils when the battery circuit is opened. S S are the line batteries and
TT are the receiving instruments along the telegraphic lines at various distances
from the transmitting instruments. U U are condensers in connection with the
telegraph lines to receive the discharge from them and prevent sparking at the
contacts. V is a finger key-one of the series of keys of the key transmitter ; when
put down it serves to stop the pin barrel F at the starting point; this however is
the repeat key and it has also other functions.
W is a handle or turn button which by being moved to the left serves mechanically
to retain the finger key V in the depressed position and it also permanently opens
the circuit of the battery P..
I will now proceed to trace in detail the battery circuits.
Assuming in the first instance that the wheel D is in such a position that tho
contact spring E¹ is resting upon its surface then the circuit of the local battery P
may be traced as follows.
From the axis C through the wheel D and spring E¹ to the block X³ thence
through the coils of the relays in the horizontal row R³ through the battery P to
the block X' so to the turn button W and the metallic plate on which it bears
and this as will be seen is connected with C the point at which we commenced to
traco the circuit.
As the axis C moves round the contact spring E¹ passes out of connection with
the wheel D and immediately afterwards the circuit is again closed through the
contact spring E². The current may now be traced as follows:-By the axis C the
disc D contact spring E2 block X2 the relays in the horizontal row R¹ the battery P
and thence back to C as before. Thus it will be seen that the continued rotation
of the axis C alternately makes and breaks the circuit of the battery P and the
currents pass alternately through the coils of the relays in the horizontal row R¹
and those of the relays in the horizontal row R².
If now by depressing a finger key the axis C be stopped whilst the spring E¹ or
E' is in contact with the wheel D (and it is never stopped at any other time) the
current of the battery will continue to flow through the coils of the relays
corresponding to the spring in contact. This when working will go on so long as
the wheel D is held stationary by the finger key if in the meantime the repeat key V
is also put down. The effect is to place the relays R³ also in circuit.
The use of this is hereinafter described.
The circuit closed by the depression of the repeat key V may be traced in detail
as follows:- Commencing at the battery P to the block X the turn button W
the block W the arm V¹ on the key (which is then in contact with W') the
block X the relays in the horizontal row R³ and thence back to the battery.
I will now trace the main line circuit No 1 commencing on the right of the diagram
at the point marked E indicating earth connection-it passes through the coils of the
receiving instruments T. T. through the line test box to the armature lever of the
relay Rs in the vertical row. N° 1 corresponding to this No 1 circuit. This armature
being against its stop the circuit is traced onwards through the stop to the contact
stops of the relays. R'. R². in the same vertical row. If neither of these armatures
be against its stop which momentarily happens when neither of the springs E¹ E
is upon the-wheel D.the circuit open. Assume however that E2 is upon the wheel
then as has already been traced the current of the local battery P is traversing the
coils of the Relays R' and the armatures of these relays will be against their stops. 5
The main circuit can now be traced onwards through the armature lever into the

page_text: battery test box and thence to the battery at Cul through the battery to the earth
connection E on the left hand of the diagram.
Supposing that in place of the relay R' the armature of the relay R³ had been
on its stop then the circuit would. be traced on from the armature of the relay R¹³
to the battery test box, the battery S at Z' and through the battery to earth as
before. So that as will be seen, in either case the line circuit is complete through
the main battery, but in the one case with the zinc pole and in the other case with
the copper pole of the battery to earth.
The circuit No 2 may be traced in the same manner but it meets the battery at
the points Cu and Z³ for the battery power is proportioned to the resistance of the
circuit.
The receiving instruments T are telegraphic printers each has a type wheel which
is caused to rotate by an electro magnetic propellment actuated by the alternato
currents resulting from the continuous rotation of the disc D.
:
By well known mechanism when a pause takes place in the continuous rotation
of the type wheel, a strip of paper is raised into contact with it and the lowest
type on the wheel prints its mark upon the paper. The type wheel makes one
complete revolution for each revolution of the wheel D. When the wheel in the
transmitter revolves the type wheel in the receiver also revolves; when the wheel D
stops, the type wheel also stops; each change of polarity in the line current
produces one step of the type wheel and results from a step made by the wheel D
under the control of the pin barrel F and the finger keys.
The precautions which are taken to keep the transmitter and receiver in unison
it is unnecessary hero to describe, they are well understood-It remains to explain
the influence of the repeat key V on the receiving instruments.
As we have already seen when this key is put down the relays in the line R³ are
caused to operate, they attract their armatures and draw them away from their
contact stops. Hence if the circuit of the line battery is at any time complete (in
consequence of the disc D being held in position and stationary by a finger key
corresponding to one of the letters or signs on the type wheel) putting down the
repeat key opens the circuit of the line battery and when the repeat key rises again
another impulse is given but this being of the same sign as that last sent through
the line wire, it does not alter the position of the type wheel in any of the
receiving instruments for these only move with each change of polarity in the line
current, But the repeated impulse affects the other mechanism of the receiving
instrument and causes the paper to be again raised to the type wheel, and the same
letter to be a second time printed, and it also causes the paper to be moved on a
step so that the next printing may occur upon a different spot of the paper.
Similarly by frequently depressing the key V whilst another key corresponding to
a blank in the type wheel is also held down the spacing at the end of a message can
be effected and the paper in the receiving instruments caused to move forward
Beveral steps.
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
(1.) In transmitting instruments having a barrel with pins stopped by finger keys
and a contact wheel or rotating surface, connecting the latter with the pin barrel by
a spring which (being strained when the pin barrel is stopped) reacts when the pin
barrel is liberated thereby (when the parts are already moving under the influence
of a frictional connection) putting into gear a pawl or locking instrument forming
a positive connection with the motor substantially as described.
(2.) In transmitting instruments having a barrel with pins stopped by finger
keys, the employment of two or more contact springs or fingers making contact
alternately with a contact wheel or rotating surface and transmitting currents
alternately through two series of relays substantially as described,

page_text: (3.) In such transmitting instruments the combination of condensers with the
series of relays transmitting alternate positive and negative impulses along the
series of line wires, substantially as described.
(4.) The combination of transmitting instruments substantially as described and
represented by the annexed drawings.