Improvements in Printing Telegraph Machines.
Year: 1899

page_text: Improvements in Printing Telegraph Machines.
We, THE TELESCRIPTOR SYNDICATE, LIMITED, of 34, Victoria Street, West-
minster, in the County of London, and ALFRED LYSTER SHEPARD, of 8, West
Kensington Gardens, in the same County, Electrical Engineer, do hereby declare
the nature of this invention to be as follows:-
This invention relates to printing telegraph machines, more especially to
transmitting and receiving apparatus of the kind forming the subject of Patents
No. 24076 of 1894 and No. 8809 of 1897.
The chief object of the invention is to facilitate the manipulation of such
apparatus, to synchronise the machines automatically after each word and to
notify the transmitting operator of mistakes at the receiver's end, and to prevent
a waste of battery power.
To this end the special synchronising key is omitted, and the line reversing
switch (hitherto operated by this special key) is actuated by a movable portion
of the keyboard, so arranged as to be operated when any key is depressed. The
said keyboard consists of metal key bars pivoted at one extremity on a common
axis, but insulated therefrom and from each other, each bar being in electrical
connection with its corresponding segment on the contact-ring, the other
extremities being adapted to move in a vertical sense between two parallel
contact-bars which are in electrical connection with the line battery, and are
arranged at right angles to the key bars, which latter are held against the upper
contact bar by means of springs. The contact bars are provided with alternate
insulated and metallic portions, so disposed relatively to the extremities of the
key-bars that each consecutive key-bar is alternately in contact with or is insulated
from the top bar, and on being depressed, any key that was insulated from the
top bar, becomes connected by the bottom bar and vice versa." The lower
contact bar is movable and is arranged to operate the line reversing switch in
such a manner as to cause the current to flow in the positive or normal sense,
when depressed by any key-bar. By means of a catch, the movable bar is held
down when once depressed and is only released by the space-key-bar, which is
adapted to release the catch, in which case the lower bar returns to its former
position by means of suitable springs; the line reversing switch is moved, at the
same time, by the bar, and reverses the current to the negative or synchro sense.
The space key is normally in contact with a metallic portion on the upper contact-
bar, and is provided with a spring contact adapted to rub against a metal bracket
fixed to the upper bar, with the object of prolonging the contact between the
said upper bar and the space key-bar (when the latter is depressed) until the
Tine current has been reversed by the switch, after which the spring contact
leaves the metal bracket and the line current is broken; on releasing the space
key the spring-contact having regard to its shape and to the form of the bracket

page_text: passes on the opposite side of the said bracket, which side is insulated, so that
the line circuit is not established until the space key-bar once more touches the
upper contact-bar, and then only in the negative sense due to the reversing
switch having been moved by the lower bar in ascending to the negative or
synchro position, in which case the space-key corresponding to the zero position
on the contact ring, and the local battery being cut off as in the machines
described in the specifications of the former patents, the transmitting machine
instantly stops.
Should the receiving machine get "out of step" during the transmission of a
message, the means employed for automatically bringing the receiver to the
zero position after the transmitter has stopped at zero at the end of a word and
for warning the operator at the transmitting end when a word has not been
properly received, consist of two sets of contacts, one for the line and one for the
local battery circuits, operated by a polarised line relay, and so arranged that
when the transmitter is arrested at zero by pressing the space-key, and in which
case a negative current continues to flow over the line, the key-board and contact
ring of the receiver which (while receiving) are normally cut out, are thrown
into the line circuit, so that the negative current arriving uninterrupted by the
transmitter from the transmitter line battery, produces the same effect as if the
receiver was working independently on short circuit, but with the line battery at a
distance, in which case the receiver runs on until the zero position is reached,
when, the local battery being cut off, the receiver stops. The interruptions thus
produced by the receiver in the negative current flowing from the transmitter
line battery, are made use of to warn the operator at the transmitting end by
means of a single stroke bell or any suitable indicator, that the receiver had
continued to run after the transmitter had stopped at zero and that consequently
the last word was badly received and should be repeated.
For safeguarding the local batteries of the transmitting and receiving machines,
from being left in circuit by a faulty manipulation of the part of the operator
the means employed consist, firstly, for the escapement circuit, of a spring
contact breaker arranged in the circuit of that coil of the escapement magnet
which receives the current when the line circuit is broken and so disposed
relatively to the armature of the escapement magnet, that the circuit of the afore-
said coil is broken each time the armature is attracted thereby, but only at the
end of the beat and after the escapement has done its work. And secondly, as far
as the printing circuit is concerned, by causing the polarised relay to break this
circuit whenever the line current flows in the negative sense, and also by so
arranging the transmission and reception lever, that should the transmitting
operator omit to press the space-key at the end of a message, the movement from
transmission to reception releases the lower bar, and so causes the line reversing
switch to be moved to the negative position before the line current is cut off,
thus guarding the local batteries at either end from being left in circuit.
Dated this 9th day of February 1899.
J. C. MEWBURN & ELLIS,
55 and 56, Chancery Lane, London, Chartered Patent Agents.
grapи machines.
We, THE TELESCRIPTOR SYNDICATE LIMITED, of 32 (late 34), Victoria Street,
Westminster, in the County of London, and ALFRED LYSTER SHEPARD, of 8, West
Kensington Gardens, in the same County, Electrical Engineer do hereby
declare the nature of this invention and in what manner the same is to be per-

page_text: formed, to be particularly described and ascertained in and by the following
statement:
This invention relates to printing telegraph machines, more especially to
transmitting and receiving apparatus of the kind forming the subject of l'atents
No. 24,076 of 1894, and No. 8,809 of 1897 which transmitting and receiving
apparatus are counterparts one of the other and in each of which on a common
clockwork driven shaft are mounted an escapement wheel, controlled by an
escapement magnet energised by a local battery current, a type wheel, and a
line brush, or trailer adapted to rub over a circle of insulated contacts each of
which contacts is in electrical connection with its own letter key, on a key-
board; the said keys being so arranged with reference to a line battery circuit,
that the self-controlled movement from contact to contact of the line brush sets
up alternate makes and breaks in the line battery current by reason of alternate
keys being in contact with or insulated from the line battery, and in which these
interruptions in the line battery current react on the escapement magnets of both
the transmitting and receiving machine through line relays, as to render the
advancement of the typewheels automatic and continuous; and in which (when
any key on the key-board of the transmitter is depressed) the function of the key
is reversed; that is to say, a key normally in connection with the line battery
becomes (when depressed) insulated therefrom, and a key normally insulated
from the line battery becomes connected therewith, so that on pressing any
key the sequence of makes and breaks becomes interrupted at this point, and
when the line brush of the transmitter arrives at the contact corresponding to
the key pressed, its automatic advance ceases, by reason of two impulses of a like
nature either makes or breaks-coming together, and the typewheels are arrested
at a point corresponding to the key pressed. In the event, however, of the
receiving machine not being in step" i.c., the two type wheels not stopping
at the same letter-it is necessary to synchronise or put them in step." For
this purpose in machines of the above description-a special knob, push or the
like actuating a reversing switch has hitherto been manipulated by the trans-.
mitting operator, at the beginning and end of a message, by means of which the
direction of the interrupted line current is reversed, and acting on polarized line
relays, switches the local battery current on both machines through a special
brush fixed to and revolving with the type wheel shaft, and rubbing round.
contact ring (connected to the local battery) having at one point (called the zero
point) an insulated portion. When the local battery brush of the transmitter
arrives at this zero point, the local battery current being cut off, it stops, and the
receiving machine no longer receiving line impulses stops also, but not necessarily
In order to bring it to zero, it has hitherto been necessary-either to
again actuate the reversing switch, or to make use of a device which allows the
local battery current of the transmitter to be broken only at the second turn of
the brush, when the line current is in the reverse direction, to allow the receiver
to stop at the zero point first.
at zero.
The chief objects of the present invention are to facilitate the manipulation
of such apparatus by synchronising the machines automatically after each word;
to notify the transmitting operator of mistakes at the receiver's end; and to
prevent a waste of battery power.
The invention will be fully understood on reference to the accompanying
drawings in which Figure 1 is a diagrammatic view in part perspective, showing
tae improved apparatus and connections arranged for transmission while Figure 2
is a similar view of the apparatus and connections arranged for receiving.
The single arrows in the figures indicate the direction of the line battery
current. The double headed arrows shown in Figure 1 (transmitter) indicate
the direction of return of the current from the earth terminal to the transmitter
line battery.
According to the present invention the special synchronising key hitherto
employed is omitted as above mentioned and the line reversing switch A (hitherto

page_text: etc.),
The
operated by this special key) is actuated by a movable portion of the key-board B
which is so arranged as to be operated when any key is depressed. The said key-
board consists of metal key bars (1, 2, 3, 4, etc.) pivoted at one extremity on a
common axis C, but insulated therefrom and from each other each bar being in
electrical connection as shown with its corresponding segment (1, 2, 3, 4
of the contact ring K, the other extremities of the key bars being adapted to
move in a vertical sense between the contact bar B and a contact bar D, which
are parallel to each other and are in electrical connection with the line battery a,
and are arranged at right angles to the key bars (1, 2, 3, 4. . . etc.) which latter
are normally held against the upper contact bar 1) by means of springs a.
contact bars B and D are provided with alternate insulated and metallic portions,
the insulated portions being shown in full black. These insulated and metallic
portions are so disposed relatively to the extremities of the key bars (1, 2, 3, 4)
that each consecutive key bar is alternately in contact with or is insulated from
the top bar, and on being depressed, any key that was insulated from the top
bar, becomes connected by the bottom bar, and vice versa." The lower contact
bar B is movable and is arranged to operate the line reversing switch A in such
a manner as to cause the current to flow out to line a¹ in the positive or normal
sense, when depressed by any key bar. By means of a spring catch E or the
like, the movable bar B is held down when once depressed and is only released
by the space-key-bar 1 which is adapted, when depressed, to release the catch E
by pushing the nose of the catch out of engagement with the bar B (as shown
in Figure 2), in which case the lower bar B returns to its former position under the
action of suitable springs F; the line reversing switch A is moved at the same
time by the bar B and reverses the current to the negative or what we may call
the synchro sense. The space-key-bar 1 is normally in contact with a metallic
portion of the upper contact bar D, and is provided with a spring contact H
adapted to rub against a metal bracket J fixed to the upper bar D with the object
of prolonging the contact between the said upper bar and the space-key-bar (when
the latter is depressed) until the line current has been reversed by the switch A
under the action of the bar B, after which the spring contact H leaves the metal
bracket J and the line current is broken; on releasing the space-key 1 the spring
contact H having regard to its shape and to the form of the bracket J passes on
the opposite side of the said bracket to that over which it rubbed in its descent,
which opposite side is insulated, so that the line circuit is not established until
the space-key-bar once more touches the upper contact bar D, and then only
in the negative sense due to the reversing switch A having been moved by the
lower bar B in ascending to the negative or synchro position, in which case the
current of the local battery b instead of flowing in the normal manner through the
tongue T and the contacts M and N of the line relay R to the escapement coils M¹
and N which control the escapement d and from thence by way of the contact U
on the positive side of the polarized relay P, and thence uninterruptedly back to
the negative pole of the local battery, now (by reason of the polarized arm P¹ of
the relay Phaving been moved by the negative current to the opposite or
negative side) passes to the local battery contact ring L whence it would
ordinarily pass by the brushes L' L2 back to the negative pole of the local battery,
but as the zero contact Z coincides with the position of the space contact 1 on the
line contact ring K, it follows that after the space key is pressed and released,
the brush L rests upon the contact Z, and the local battery current is therefore
broken at this point, and the machine consequently stops, until any other key
is depressed, in which case the line reversing switch A is once more moved to
the positive position, and the local battery current being thus re-established
through the contact U, the machine commences to revolve.
e is a corrugated wheel and el a pallet spring carrying a stud adapted to engage
in said wheel whereby the current of the local battery is alternately opened and
closed through the printing electro magnet f as described in the said previous
specification's to effect the impression by the type wheel g.

page_text: Should the receiving machine get "out of step" during the transmission of
a message, the following means are employed for automatically bringing the
receiver to the zero position, by allowing it to run on alone after the transmitter
has stopped at zero at the end of a word, and for warning the operator at the
transmitting end when a word has not been properly received. The polarized
relay P controls two sets of contacts. On the positive side are:-I, the printing
circuit contact, and U the local battery cut off contact already described. On
the negative side are the three contact springs V, W and Y of which W is con-
nected directly to the carth terminal c of the line return, V is connected to the
line battery a through the reversing switch A and Y is connected to the line
battery, not directly, but through the keyboard and contact ring K. The
operation of these contacts is shown in Figure 2 of the diagram, which represents
a machine receiving an uninterrupted negative current from the distant trans-
mitting line battery, due to the transmitting operator having just arrested the
transmitting machine at zero, by pressing the space-key, and releasing the same
after the space had been printed. The switch Q is in the receiving. position.
The arm of the polarized relay P' has been moved by the negative current
to the () negative side. The spring W is consequently in contact with Y, and
insulated from V. In this case the line current arriving uninterruptedly from the
transmitter in the negative sense enters the receiver at the earth terminal c
instead of the line terminal a, and (by following the arrows) will be seen to pass
through contact spring W to contact spring Y from there to the revolving line
brush K¹ and from there by way of the contacts to the key bars 1, 2, 3, 4,
At this point the current is alternately made and broken, according to whether
the bar over whose section the brush K' is passing, is insulated from or in
contact with the bar 1). From 1) the current passes by the reversing switch A
to the switch Q, whence it passes through the coils of the line relay R and the
polarized relay P back again to the switch Q and out to the line terminal a' back
to the transmitting machine.
etc.
From the above it will be seen that when a negative current is sent to the
receiving machine the key board and contacts (normally cut out while receiving)
are thrown by the polarized relay into line circuit, so that the negative current
arriving (uninterrupted by the transmitter) from the transmitter line battery,
produces the same effect as if the receiver was working independently on short
circuit, but with the line battery at a distance, in which case the receiver runs
on until the zero position is reached, when (the local battery being cut off) the
receiver stops. The interruptions thus produced by the receiver in the negative
current flowing from the transmitter line battery, (after the transmitter has
stopped at zero) are made use of to warn the operator at the transmitting end
by means of the single stroke bell y shown in the diagram or other suitable
device, that the receiver had continued to run after the transmitter had stopped at
the space or zero point, and that consequently the last word was badly received
and should be repeated. The bell is wound with a high resistance for the purpose
hereinafter described, and has a hammer arranged to strike the gong when the
bell current is cut off. One end of the bell circuit is connected to the zero con-
tact and the other end to the negative terminal of the local battery.
It will be seen from Figure 2 that the bell circuit is only completed when the
local circuit brush L' comes upon the zero contact Z, and also that when a positive
line current is flowing through the coils of the polarized relay P' and the arm 1"1
is consequently on the positive side, the bell is short circuited by the contact of U
and P. When, however, a negative current flows in the line, as-for example--
atter pressing and releasing the zero, or space-key, then the contact between U
and I being broken the local current flows by the tongue T and the contact M
of the relay R through the coil M to the local battery brushes L2 L to the con-
tact Z, from here through the bell coil to the negative terminal of the local
battery, thereby raising the hammer from the gong. The current flowing
through M¹ is not strong enough, owing to the high resistance of the bell coil to

page_text: move the escapement arm, so that if both machines are in step, on releasing the
space key both machines remain at zero, and the bell does not sound; should,
however, the receiver be out of step with the transmitter, it will continue to run
on, alone as has already been explained, and the interruptions caused by its so
running in the negative current flowing from the transmitting battery, will
cause the tongue T of the relay R to oscillate between the contacts M and N,
and the intermittent local currents thus produced in the bell circuit, while not
strong enough to move the escapement arm, give repeated strokes on the gong,
according to the number of contacts that the receiver may be behind the trans-
mitter.
For safeguarding the local batteries of the transmitting and receiving machines
from being left in circuit should the line current of the transmitter (by a faulty
manipulation on the part of the operator) be broken by the switch Q before the
brush L had reached the zero point; the means employed consist, firstly for the
escapement circuit, of a spring contact breaker N2 arranged in the circuit of that
coil N of the escapement magnet which receives the current when the line
circuit is broken and so disposed relatively to the armature of the escapement
magnet, that the circuit of the aforesaid coil is broken each time the armature
is attracted thereby, but only at the end of the beat and after the escapement has
done its work. The action of this contact breaker shown in the drawings will be
readily understood from the figures. It comprises a fixed plate and a spring
plate insulated from each other by an insulating block 2. Contacts ³n on
the respective plates allow the current to pass at the proper times to the coil N¹,
but when the armature () is attracted by the coil N¹ a cam N on the tail of said
armature forces the plate n¹ out of contact with and breaks the circuit of coil N1
as described. Secondly, for preventing the local batteries from being left in
circuit as before referred to by faulty manipulation, as far as the printing circuit
is concerned, the arm 1" of the polarized relay P is caused to break this circuit
at I whenever the line current flows in the negative sense, and also the lever of
the transmission and reception switch Q is so arranged that, should the trans-
mitting operator omit to press the space key at the end of the message, thereby
causing the line current to flow in the negative sense, the movement of the
switch Q from transmission to reception releases the lower bar B by pushing
back the catch E through the intermediation of suitable means, and so causing
the line reversing switch A to be moved under the action of the bar B to the
negative position before the line current is cut off, thus guarding the local
batteries at either end from being left in circuit.
Having now particularly described and ascertained the nature of our said in-
vention and in what manner the same is to be performed, we declare that what
we claim is:―
1. In a printing telegraph machine of the kind herein referred to, the employ-
ment of a movable portion of the keyboard so disposed relatively to the keys and
to the line current reversing switch that when any key is depressed the reversing
switch commutes the line current to the positive or normal working sense, and
a retaining device, adapted to retain said movable portion of the key-board,
and thereby also said switch, in the commuting position against the action of
a spring or springs until the space or zero key is depressed and released, said
retaining device being thrown out of engagement by the depression of the space
key, whereupon said movable portion of the keyboard and said reversing switch
return to their original positions and the line current is reversed to the negative
sense, the use of a special synchronizing device as before referred to being thus
obviated and whereby synchronism of transmitter and receiver may be automatic-
ally established or ensured at each depression of the space key, substantially as
described.
2. In a printing telegraph machine of the kind herein referred to, the utiliza-
tion of the polarized relay to actuate a special switch by means of which a negative

page_text: or synchronising current arriving from the transmitter is caused to pass through
the key-board and line contact ring of the receiving machine, so that the re-
ceiving machine (if out of "step") continues to revolve after the transmitter has
stopped at zero, substantially as described and shown, and for the purpose
specified.
3. In connection with a printing telegraph machine as above described, a signal
bell or other like device arranged and connected substantially as described,
whereby if, at any depression and release of the transmitting space key the trans-
mitter and receiver are out of step, the operator by the act of depressing and
releasing his space-key is warned that the last word was not properly received
at the other end, the said bell or other device being operated through the medium
of the interruptions in the negative current that flows to line when the trans-
mitting machine is arrested at zero, caused by the rotation of the receiving
machine on its way to the zero point, substantially as described and shown.
4. In a printing telegraph machine driven by an escapement which is worked
by two magnet coils in the manner herein described, a spring contact breaker
arranged in the circuit of that coil of the escapement magnet which receives the
current when the line circuit is broken, and so disposed relatively to the armature
of the escapement magnet that the circuit of the aforesaid coil is broken each
time the armature is attracted thereby, but only at the end of the beat and after
the escapement has done its work, substantially as described and shown.
5. In a printing telegraph machine of the kind herein referred to, the safe-
guarding of the local battery so far as the printing circuit is concerned--by
causing the polarized relay to break this circuit whenever the line current flows
in the negative sense, substantially as shown and described.
6. In a printing telegraph machine of the kind described in this specification,
the arrangement of the transmission or reception switch. in such manner that the
movement from transmission to reception--at the end of a message-effects the
movement of the line reversing switch to the negative position before the line
current is cut off, substantially as described.
7. The improved printing telegraph apparatus substantially as described and
shown in the accompanying drawings.
71 1
J. C. MEWBURN & ELLIS,
55 and 56, Chancery Lane, London, Chartered Patent Agents.