Year: 1889

page_text: Date of Application, 29th Jan., 1889
Specification Accepted, 2nd Mar., 1889
I, MARK WESLEY DEWEY, of the City of Syracuse, in the County of Onondaga,
in the State of New York, United States of Amorica, Inventor, do hereby declare the
nature of my invention and in what manner the same is he performed, to bo
particularly described and ascertained in and by the following statement:-
My invention relates to an electric telegraph adapted for the simultaneous trans-
mission of four distinct and separate mossages on one line wire to produce which
currents differing in polarity and intensity are used.
This improvement consists in so combining several sections of battery with three
single-current transmitters or keys and one double current or pole-changing
transmitter or key that when a certain key or keys are operated they will send
currents to line that will select and operate the corresponding receiving instrument
or instruments and no other.
It also consists of the combination of seven neutral relays, described below,
whereby three sounders or registers may be properly operated by the threo single
current transmitters, and one polarized relay which operates independently another
sounder or register whenever the current is reversed by the double current
transmitter.
That this invention may be more clearly comprehended I have in the annexed
drawings endeavored to illustrate the same fully and will describe it, referring
to them.
This
In the drawings, Figs. 1 and 2 show two forms of apparatus differing slightly
from each other in arrangement but not in principle. In both figures four trans-
mitters are represented, three of them as before stated, are known as single
transmitters and the other a double transmitter or pole changer. When all the
transmitters are at rest, or in their inoperative position a comparatively weak current
of a certain polarity from battery 20 6, continually flows to line, the same as all the
single transmitters send to line when operated without the double transmitter.
is sufficient to operate the polarized relay when the double current transmitter-T—
is used alone, closing its local circuit through sounder-S-only when current
through line is reversed, or according to drawings, whenever a positive current flows
to line. This strength is not sufficient to move the neutral relays on account of
their retractile springs, therefore, they will only respond when currents of greater
strength are sent to line by the single transmitters-T-T-T-Each single
transmitter has the independent control of a separate battery. In Fig. 1 of the

page_text: Drawing, T-controls a lattery of the same strength of that already to line
indicated by 20, B,-T-controls a battery of greater strength indicated by 30 B,
and T-controls battery 40, B, of still greater strength. The difference of the
numbers indicate the difference in the strength.
I do not limit myself specifically to the various strengths of the aforesaid batteries
indicated in the annexed drawings, it being only necessary that enough difference
should exist to give the required margin for the adjustment of the neutral relays at
the remote station.
If transmitters-T-T-T³-are open, twenty cells of battery 20 b, are in
circuit subject to the control of pole-changing transmitter-T-In this case the
route from line to ground will be through magnets of relays, then to support of
contact points of T-springs--then to T-by wire-u-to hook-h;
spring-wire-w-to-T,-hook-,-spring-s-by wire-w-to-T-hook
h, springs,—wire—w³. -to battery 20, b, spring-s-T-by wire-w-to
ground-G. When the double transmitter-T-is open the negative current is
to line, if closed the positive current, transposing the route of the battery 20 b.
When the negative is to line the armature of the polarized relay P, R, is held
to open the local circuit through sounder-S, and if the polarity is changed
to positive, the armature will move to close the local circuit through said sounder.
It will be observed that all line currents pass via T, and when said transmitter
is open or in its normal position, the negative current is to line under any
or all conditions that the single transmitters may be placed in i therefore the
polarized relay P, R, will only respond to the movement of the double current
transmitter--and will do so whatever the strength of the battery may be in
circuit at the time.
-
Referring as before to Fig. 1 of the drawing, if-T-is depressed, battery 20 B,
is in circuit with that already to line which equals 40 and is of sufficient strength
to move the tongue of neutral relay-R-to contact of lever--but is insufficient
to overcome the tension of spring--and therefore closes the local circuit operating
sounder-S¹.
The circuit from local battery-1-in this case is by wire-e-to stop-i,-
armature-lever of relay-R',-wire-c,-through sounder-S'-returning to battery.
The other relays 1, 2, 3 etc., are unable to move because the current is not of
sufficient strength to overcome their retractile springs.
If T is depressed alone, battery 30 B will be in circuit with the 206
equaling 50 and is sufficient to move the tongue of relay-2-to contact of its
lever and relay-1-will move its lever--to break the circuit controlled
by it because the strength of current is sufficient to overconio the spring-of
lever and break contact with stop-i,-but is not sufficient to overcome
rectractile spring of lever--of relay-2,-therefore the local circuit is closed
through sounder-S.
The route of current in this local circuit is from battery-2,-wire-
to stop-i, lever-,-armature lever of relay-2,-wire--through sounder
-S and return to the battery. It will be noticed that when the armature
lover of relay-2,-moves, lever---moves with it to break a shunt wire
commencing from between battery and sounder-S2-and extending by
wire through contact levers--of relays 2, 3, and 6, wire--to
wire-d'-. This serves to shunt sounder-S-when necessary, and for the
purpose hereinafter explained. The lovers--are insulated from the armature
levers of the relays.
When T-is closed alone battery 40 B is in circuit with the 206 making 60
which will move armature lever of-R³-to its contact lever-1-but not farther
on account of retractile spring-closing its local circuit through sounder-S³-
by wire-e, stop, contact-lover and armature lover of relay-R³,-wire-e-
through sounder-S-to battery. In this case both relays 1 and 2 have moved to
their extreme condition, thus their local circuits are open but the shunt mentioned
above is closed through lever--and stop-n' of relay-2.

page_text: When T-and-T-are closed simultaneously batteries 20 B and 30 B with
the 20 are in circuit making a strength of 70; this serves to move the armature
lever of relay-4-to contact point of its lover--closing the circuit through
sounders Sand-S³,- and opens the shunt by means of its lever――so that
-S-will not be shunted.
•
Relays 1, 2 and 3 have moved to their extreme condition breaking their circuits
through their contacts. The current in this case is from battery-₁₁-wire--1-
and to stop i,-lever-,-armature of relay-4,-wire-fi
through S-battery-,-wire-d-to-f-sounder-S'-and return to battery
→1.
When T-and-T³-arc depressed together and--open, 20 B, 40 B,
and 206 = 80 is in circuit and is sufficient to move armature lever of relay-R*,-
to contact point of its lever--closing a circuit through sounders-S'-and
-S-There is no lover--on this relay and the other relays 1, 2, 3 and 4
having moved to their extreme position, the shunt is therefore closed so that
sounder S-is cut out and will not respond. The route of this circuit is from
battery-b-wire-c-f ―to stop-of relay R, contact lever-,
armature lever, wire-g-e-through sounder-S³,-battery-63,-wire—e—d¹¹.
lever of relay--thon to "stop-n',-lever--of relay-R', then to
-n-1 of relay-R²,-wire-d"-to battery-62-wire-d-f-sounder-S¹-
and return to-b¹.
When transmitters-T-and-T³-are both closed and-T-open, 30 B, 40 B
and 20 b
90, are in circuit and cause the tongue of relay-6-to come in
and contact with its lever--closing the local circuit through sounders-S²-
-S³.
=
It will be understood of course that all the relays adjusted to respond to weaker
currents have moved to their extreme position thereby breaking the circuits through
their contact points, stops-i-and levers-1,-but closing the shunt between
stops-n--and lever-,-but as it is necessary to have the shunt broken in
this case, in order to have-S-in circuit, relay 6-breaks it between stop-n-
and lover. The current through local circuit flows from battery-²,-
wire-d-j-stop-i,-lever--and armaturo lever or relay-R-wire-ji-
to e, agnet of-S³,-battery-³,-wire-e-d-d',-sounder-S² to battery
When the armatures of the relays pass over from one extreme position to the
othor, it will be observed that the local circuit is closed for an instant, but not
long enough to produce any effect whatever upon the levers of sounders.
When transmitters-T₁_T²-and-T³-aro closed all the batteries are in
circuit equaling 110. This is sufficient to move the 7th and last neutral relay to its
extreme position with the others, closing circuit through all the sounders of neutral
relays S-S-and-S³:
-
-d',
The local current flows from battery-b',-wire-c-f,-stop-o,-armature lever
of relay-7,-wire-k-e-S³,-battery-63,-wire-e,
-S³,-
battery -wire-d-ƒ³— —c¹— —S³—and return to battery-b'. The shunt
being broken between stop-n-and lever-l-of relay-6- allows sounder-S³—
to respond.
It will be understood that if transmitter-T-be operated a reversal of tho
different strengths will always actuate the polarized relay and sounder-S*.
By the above it will be also noticed that there are sixteen electrical conditions of
the line corresponding with the sixteen possible positions of keys at transmitting
station.
It is obvious from the arrangement of the apparatus as shown in the annexol
drawing, that four separate messages may be simultaneously transmitted over a
single wire in the same direction, and, in order that eigh imessages may simultaneously
pass over a single wire, it is only necessary to have a set of transmitting and receiving
instruments at each end of the line, properly constructed in any well known manner
for simultaneous transmission in opposite directions, or the entire number of trans-
mittors at a station may be used simultaneously to transmit to another station a

page_text: single message in accordance with the plan described in a former application for
Letters Patent No. 18,900 A.D. 1888 for an improvement in Telegraphy, in Great
Britain.
.
On this plan two messages may be transmitted at the same time one in each
direction, and two operators are enabled to perform the work of eight in the same
length of time. Fig. 2 of the drawing shows a modification of the hereinbefore
described arrangement whereby a greater difference in strength sent to line is
derived, giving more margin for the adjustment of relays at receiving station, and
the relays are simplified, having but one contact lever--which allows the armaturo
to move more freely. In this case there should be two magnets to each sounder
governed by the noutral relays, or the magnets have double helices as shown in
drawing. This is done in order to properly select the sounders or registers as the
case may be, for there is no shunt wire in this plan to cut out sounder-S²-as
will be observed, and the local circuits are somewhat different from those shown in
Fig. 1 of the drawing. The principal difference in the transmitting apparatus is
that there is what might be called a fragment of the line wire which contains a
battery and is included in the circuit only whenever the first and second transmitters,
first and third, or first, second and third transmitters are closed together. This
fragment of line wire is connected by means of a second contact spring on each
single transmitter and contact point, as shown.
In the transmitting apparatus the strength of each section of main battery is marked
in the drawing to wit: one of 20, two of 40, one 80 another 120. The different
strengths sent to line are also marked near the relays which they govern, and the
number of the transmitter or transmitters that send it, and the sounders are numbered
to correspond with the transmitters and respond only when their corresponding
transmitter is depressed at the distant station.
The routes of local currents in this plan are: when 60 cells are in circuit through
main line, relay .1 responds as in the other plan, the armature lover moving to its
contact lever, but no farther on account of the retractile spring of lover-1.
The current flows from local battery-',-lever-l,-armature lever of relay, to
lower section of helicies of sounder-S-to battery. The relays respond in the
same manner as those in the other receiving apparatus with the exception that in
Fig. 2 of the drawing there is no shunt and the contact levers--are omitted,
and whenever any of the first five neutral relays respond without the two others 6
and 7, the local currents flow through the lower sections of helices of sounders, and
when either of the last relays-7-and-8-respond the current flows through.the
upper section of helices of sounders, from either or both batteries-6-and-;-
when-6-moves to close its circuit battery-6-only is in circuit and when
relay 7 closes its circuit both--and---are in circuit.
The description of the operation of the polarized relay in the first.described plan
applies, also to the modified arrangement.
•
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-The combination at one station of the telegraph line with its weak battery in
constant circuit, of four transmitters, four batteries of different strengths, each of
the latter being controlled separately by one of said transmitters, and eight relays at
another station controlling four registers or sounders, substantially as specified.
2-The combination at one station of three single current transmitters, soveral
batteries of different strengths, each of the latter being controlled separately by one
of said transmitters, and seven relays at another station controlling three sounders or
registers as set forth.
3-The combination at a receiving station of seven relays adapted to be operated
by currents of different strengths, sent from another station through a single line
wire, the levers--and and contact stops-i-controlling three sounders and a ¦
polarized relay controlling a separate sounder, substantially as specified.

page_text: 4-In a system of multiplex telegraphy having a single line wire, the combination
at the receiving station of soven relays differently adjusted and actuated by currents
of different strength, their contact levers-1,-stops-i,-contact levers-,-
stops-n-and--and their respective local circuits, batteries and sounders, sub-
stantially as specified.
5-In a system of multiplex telegraphy having a single line wire, the combination
at the receiving end, of seven relays differently adjusted and actuated by currents of
different strengths sent from a distant station, their contact levers-1,-stops-i,-
contact levers,-stops-n-and-n',-their respective hattories and sounders and
the polarized relay controlling a separato sounder or register by a separato local
circuit, substantially as specified.
6-The combination of three single transmitters at one station, a portion of main
line containing on its circuit a section of a battery that forms part of the main line
only when two or more of said transmitters are closed simultaneously, the batteries of
different strengths and the neutral relays controlling the sounders at the receiving
station, substantially as set forth.
7-In a multiplex telegraph, a single main line in combination with a series of
batteries of different strengtlis at the transmitting end of the line, a series of trans-
mitting keys corresponding to said batteries, and each of which is adapted to couple
its battery in the line circuit, a series of sounders or registers at the receiving end of
the line corresponding to said transmitters, a serios of relays in circuit with the main
line and corresponding in number to the possible combinations of the transmitting
keys, springs to hold the armatures of the relays back and corresponding in strength
to the strength of the possible combinations of the batteries, local batteries for the
sounders or registers and local circuits for said sounders or registers controlled by said
relays whereby the proper sounders or registers will respond for given keys.
8 In a multiplex telegraph the combination of a main line, a line battery of low
tension always in line, a series of batteries of different strengths at the transmitting
end of the line, a series of continuity preserving single current transmitters or keys
corresponding to the said last mentioned batteries and adapted to put one or more of
said batteries to line according as to the number of said transmitters or keys put into
action at one time, a continuity preserving double transmitter or key also at said
transmitting end of the line and adapted to reverse the current in the line, a series
of sounders or registers at the receiving end of the line and corresponding in
numbers to the transmitters or keys, a series of relays arranged in the main line
circuit and corresponding in numbers to the possible combinations of the continuity
preserving single current transmitters and adapted to respond to currents of different
strength, but greater strength than the current which always traverses the main line
from the low tension battery, a polarized relay in series with the relays above
mentioned and adapted to respond to the reversals of the low tension current which
normally traverses the main line and which is controlled by the continuity preserving
double transmitter and a series of local circuits between said sounders or registers
and all of the relays and controlled by said relays whereby the sounder or register
corresponding to each transmitter or key shall sound or register upon the operation of
said transmitter and irrespective of the operations of the other transmitters.
9-In a multiplex telegraph the main line over which a current is normally flowing
and which current is varied in strength and polarity in combination with suitable
receiving instruments at the receiving end, and the following transmitting instruments
at the transmitting end, to wit: Three continuity preserving single current transmitters,
three batteries of different strengths, each of which is adapted to be put into the line
circuit by its corresponding transmitter, a continuity preserving double transmitter
for reversing the current passing to line, and a line battery of less strength than the
other batteries always in circuit with the line and controlled as to its polarity by the
double transmitter.
10 In a multiplex telegraph the main line over which a current is normally
flowing and which current is varied in strength and polarity, in combination with
suitable receiving instruments at the receiving end, and the following transmitting

page_text: instruments at the transmitting end, to wit:-three continuity preserving single
current transmitters, three batteries of different strengths, each of which is adapted
to be put into the line circuit by its corresponding transmitter, a continuity proserving
double transmitter for roversing the current passing to line and a line battery of less
strength than the other batteries, always in circuit with the line and controlled as to
its polarity by the double transmitter, and a fifth battery equal to or substantially
equal to the strength of the weakest battery controlled by the single transmitters and
adapted to be put into line circuit only when the single transmitters controlling
the weakest and one or more of the stronger batteries are simultaneously closed,
to cause the variations in strength of the current flowing in the line to vary
uniformly.
11 In a multiplex telegraph the main lino over which a current is normally
flowing and transmitting instruments at the transmitting ond of the line consisting
of threo single current transmitters and three batteries of differing strength, each
battery adapted to be put into line circuit by its corresponding transmitter for
varying the strength of the current in the line in a predetermined manner in com-
bination with a series of sounders or registers at the receiving end of the line, a
series of relays also at said ond of the line in the line circuit and equal in number to
the possible combination of tho sounders or registers and adapted to respond to
currents of different strength, local batteries and connecting local circuits including
said sounders or registers and batteries, and controlled by the relays.
12 In a multiplex telegraph the main line over which a current is normally
flowing, and transmitting instruments at the transmitting end of the line, consisting
of three single current transmitters and three batteries of differing strength, ench
battery adapted to be put into line circuit by its corresponding transmitter for varying
the strength of the current in the line in a predetermined manner, and a double current
transmitter for reversing the current in the line when desired, in combination with
a series of sounders or registers at the receiving end of the line, a series of relays
also at said end of the line in the line circuit and equal in number to the possible
combinations of the sounders or registers and adapted to respond to currents of
different strength, local batteries, and connecting local circuits including said sounders
or registers and batteries, and controlled by the relays, a polarized relay in circuit
with the above mentioned relays and line, a sounder or register for said polarized
relay, a local battery and a local circuit including said sounder or register and
battery and controlled by said polarized relay.
13-The combination at the receiving station of the line circuit conveying currents
of different strengths, with soven relays adapted to be operated by currents of
different strengths sent from another station through the line, three sounders or
registers having double windings, local batteries, seven local circuits including said.
batteries and sounders or registers and respectively controlled by said seven relays,
lovers of said relays adapted to offer different resistances to movement, and
stops i-connecting respectively with one end of the local circuits, the other ends of
which circuits connecting with the relay armature, whereby said seven relays control
tho three sounders or registers for seven variations in the line current.
Dated this 14th day of Jana 1000