IMPROVEMENTS IN ELECTRICAL SYNCHRONOUS Move- MENTS
Year: 1885

page_text: I, ALBERT LYMAN PARCELLE, of Boston, County of Suffolk, Commonwealth of
Massachusetts, United States of America, Inventor, do hereby declare the nature
of any said invention for IMPROVEMENTS IN ELECTRICAL SYNCHRONOUS Move-
MENTS and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
Electrical synchronous movements are capable of various uses, and of course I
contemplate employing my invention wherever it is applicable. An important
field for such an invention is that of multiplex telegraphic transmission of
messages, and I have therefore, as one application of my invention, shown ordinary
telegraphic keys and relays connected with insulated contacts over which circuit-
completers, carried by the synchronously moving apparatus, pass. Of course any
other suitable telegraphic apparatus other than those of the character shown may
be used.
I am aware that numerous arrangements for obtaining synchronous movements
have been patented heretofore. My invention, however, differs from all such
systems both in its general principles of operation, as well as its details of
organization.
In the accompanying drawings-
Figs. 1 and 1a are diagrammatic views illustrating two stations, X and Y
connected by a main line and equipped according to my invention.
Fig. 2 is a detailed view partly in section illustrating the motor which I prefer
to employ in working my system.
Figs. 3 and 4 are diagrams showing the travelling arms in varying positions.
In Figs. 1 and 1a two stations X and Y are shown connected by a main line.
The organizations at both stations are identical.
A vibrator A mounted at one end in a block or post A¹ carries an armature a,
arranged transversely on its free end, and acted upon by magnets B, C, having the
faces of their poles opposite the face of the armature and in a plane substantially
parallel therewith. Contacts b, c, on opposite sides of the vibrator make contact
with spring fingers b, c, in the circuit of the motor magnets B, C, to make and
break the circuit as is well understood. In addition to these contacts I also
employ switch devices D, which may be constructed as follows:-
A sliding block E is mounted on a suitable bed-plate, the sliding block being
guided and limited in its movement by two screws e which pass through slots in

page_text: the block, and are secured to the bed-plate. Two uprights or posts on the sliding
block are provided with adjusting screws el between which the vibrator A is
located. As the vibrator moves, therefore, the sliding block is shifted first to one
side and then to the other, and the exact moment of its movement may be
regulated in a measure by the adjusting screws e¹ These screws may be tipped
with rubber or cork to prevent noise.
The sliding-block carries two contact fingers F, G, (either insulated or uninsulated
from each other), which make and break contacts with posts f, g, as the vibrator
moves back and forth, and shifts the switch-block. One pole of the motor battery
L, B, is connected with the heel of the vibrator, from thence the circuit is con-
tinued through the vibrator to the platinum contacts bc, thence by either of the
springs or c¹ through the coils of either of the magnets B or C, and thence to
either of the contact fingers F or G, and contact-post for g to the opposite pole of
the battery. These circuits are shown in the drawings by dotted lines. The
circuit of the magnet B is represented by the letter b², and that of the magnet C
by the letter c².
In starting the motor into operation an impulse of vibration may be imparted
to it by the hand of the operator. Assuming that the vibrator is moving towards
and across the faces of the poles of the magnet C, the contact c will make contact
with the finger c¹ while the contact finger G of the switch devices is on the
contact face of the post g. The circuit, therefore, will be completed from the
battery L B, through the vibrator, contact c, finger c¹ coils of the magnet C, and
thence by wire c² to the finger G, post g, and opposite pole of the battery, and the
armature a will be attracted. The continued movement of the vibrator in that
direction opens the circuit just described by the shifting of the sliding-block E
which moves the finger G out of contact with the post g, and makes _contact
between the finger F and the post f in the circuit of the opposite magnet B. The
vibrator will now, by its resilience spring back and make contact between the
contact-plate b and the finger b¹, thus completing the motor circuit through the
coils of the magnet B. Under the attraction of the magnet B the vibrator con-
tinues its movement until, by the shifting of the block E, the circuit of said
magnet is opened at the contacts F. f.
I utilize the vibrating motor just described to actuate circuit-completing devices
in the following manner, see more especially figure 2. The vibrator is there shown
as rocking an anchor lever H, back and forth in its vibration. This lever is shown
as pivoted in a horizontal arm H¹, of a standard H2 which would be mounted on a
bed-plate. The lower end of the anchor-lever on which the vibrator acts is
notched, and is preferably provided with elongated lateral extensions h, which
serve as guides or guards to prevent the vibrator swinging free of the anchor-lever,
and thus ensure its proper actuation. Pitmen or push-and-pull arms H³ pivoted on
the anchor-lever carry pawls or teeth which work in a ratchet wheel H having its
bearings in the standard H. The rocking of the anchor-lever by the vibrator
causes therefore an intermittent or step-by-step rotation of the ratchet-wheel.
A circular table I, is carried by the standard H, and is supported thereon
concentrically with the axis of the ratchet-wheel H. Turning now to figs. 1, 1a
the axle of the ratchet-wheel passes through the table and carries on its outer end
an arin K which extends across the table I, and is provided at one end with a
trailing brush or finger which traverses around the table. A circular series of
independent contacts are arranged upon the table in the path of the brush k,
which makes contact with them successively.
In Figures 1, 1º the organization above described is illustrated properly con-
nected at the upper part of the figure at each station; while the lower part of the
figure diagrammatically represents the table, the trailing circuit completer, and the
electrical devices and circuits of my improved synchronous arrangement. The
vibrator motor which I have described is one well adapted for the actuation of my
synchronous movements, but I do not confine myself to its use, nor is any claim

page_text: made herein to the motor, per se, as it constitutes the subject matter of a separate
application filed by me.
In electrical synchronous systems heretofore patented it has been proposed to
actuate the apparatus independently at each station and to correct the speed of the
motive apparatus at one station by means of an impulse of electricity transmitted
from the distant station. Though I employ an independently actuated motor at
each station the correction, should the apparatus at one of the stations move too
fast, is accomplished locally by said apparatus itself, though the effect of such
correction is removed by an impulse of electricity from the distant station, and
this feature constitutes one of the peculiar characteristics of my invention.
On the table I at each station I have shown four contacts devoted to maintaining
the synchronous movement of the apparatus at the two stations. Two of these
contacts marked m, m¹, are placed one on each side of the table, though not
directly opposite each other, and are connected to earth by a wire m² through the
coil of a magnet M, as clearly shown. The other two contacts n, n' also arranged
on opposite sides of the table about midway between the contacts m m¹ though
not directly opposite each other, are connected together and by a line n² with a
main battery M B. The arm K which carries the brush or circuit completer /
extends entirely across the table of contacts, and is shown as projecting slightly
beyond the table at each end. It is so shaped that a straight line drawn from the
end to the end which carries the trailing finger would not be a true diameter of
the circle of the table of contacts, but the end carrying the trailing finger is
deflected from a true diameter, the direction of the deflection being toward the end
of the trailing brush k. This is done so that in the operation of the apparatus the
end of the trailing finger will make contact at the proper time with the plates
m m¹ and n n¹, which are placed at irregular intervals around the table, as is fully
described below.
A detent Olies normally in the path of the extended ends of the arm K, as
clearly illustrated in the drawings. This detent preferably consists of an elastic
or spring arm which is mounted and slides in a suitable frame P, for the purpose
presently described, and carries an armature o which is acted upon, as will be
described, by the magnet M. The detent arm O is constructed with a guide-pin
which slides in an eye in the frame P, and is provided with a coiled spring o³,
which tends normally to press the arm outwardly from the frame in the direction
of the magnet M. The detent O between the arms of the frame P is provided
with an enlarged face or plate o², which, when the detent is thrust back by the
impact of the arm K, as shown at X in Fig. 1, makes contact with two adjustable
contact pins c and b, mounted in, but insulated from, the frame P. The contact-
pin cis connected by a line c³ with the circuits c of the magnet Cat a point
between the coils of the magnet and the contact-finger G in said circuit, and by a
line with the circuit 2 of the magnet B. The pin b is connected by line q,
key Q, and its back stop through the coil of the magnet M to earth, as clearly
shown in the drawing. The front stop of the key is connected, as shown, with the
main battery M B. Another insulated contact-pin 7, mounted on the leg of the
frame P, opposite that which carries the pin c, is connected with the arm K, as
clearly shown. When the detent O is pushed back by the end of the arm K
abutting against it, as shown in the drawings (Fig. 1, station X,) it makes contact
by means of its plate o² with the two pins c and b, and when the detent is not in
engagement with one of the ends of the arm K its contact-plate o' is pressed by
the spring o towards the opposite leg of the frame P into contact with the
insulated contact pin (station Y, Fig. 1a), which is connected directly with the
arm K, as before mentioned. The pole of the local battery L B which is not con-
nected with the heel of the vibrator is connected as 'shown by a line 16 with the
frame P. The main line L connecting the stations is also connected at each end
with the frame P, and the frame is electrically connected with the detent O which
is carried by it. This construction is well adapted for the purpose and the various

page_text: connections properly made, but of course my invention is not limited to such
details. The purpose of these various connections will now be described.
When the contact-plate o of the detent O is in the position shown in the
drawings, at X Fig. 1, one or the other of the local motor circuits, 62 or c², will be
completed around and outside of the switch devices D, so that that circuit which
happens to be completed at the points b b¹ or c¹ will remain closed as long as the
detent remains in the position illustrated, and the vibrator will be checked or held
up towards the magnet B or C, the circuit of which is completed as just stated;
for instance, if the vibrator has swung to the right as viewed in the drawing and
makes contact between its plate c and contact-finger c¹, the motor circuit of the
motor C will be completed as follows: From the local battery L B through the
vibrator, contacts c c', coils of the magnet C, line c², c³, pin c, contact plate o² of
the detent, frame P, and by line 16 to the opposite pole of the battery, and as
long as the circuit remains closed at the pin c¹ the vibrator will be held on that
side of the center of vibration, and prevented from swinging back towards the
magnet B. The same operation would occur if the vibrator happened to be in a
position to make contact between b and b¹, and the vibrator would be held up by
the magnet B. By this means I am enabled to check or retard the speed of the
vibrator to insure the synchronous movement of the apparatus, as will more fully
appear presently. When the contact plate o2 is pressed out (which is the normal
position) by the spring so as to break contact with c and b, of course the shunts
around the switch device D are opened and the motor operates as before described.
When the contact-plate o² of the detent O is in contact with the main line pin r,
which is the normal position when the apparatus at the two stations is running
synchronously, the main line circuit will be completed from one station to the
other through the frame P, contact-plate o³, pin r, and radial arm K, to the
contacts or space between the correcting contacts m m³ and n n', and may be used
for any purpose desired.
Whenever either end of the arm K has abutted against the detent O, as shown
in the drawing, the end of the trailing finger k will be on one of the ground
contacts m m¹; for instance, take the position shown at X in Fig. 1, there the
brush end of the arm K has abutted against the detent O, and the end of the
trailing finger k is resting on the ground contact m¹. In this position the main
line circuit is completed through the frame P, detent O, arm K, ground contact m³,
and coil of the magnet M to earth. When the opposite end of the arm is against
the detent the finger k will make contact with the other ground contact m, and the
circuits are the same as just mentioned. If therefore an impulse be received from
the distant station with the arm in either of the two positions mentioned the
magnet will be energized and the detent drawn down out of the path of the pin.
With the parts as shown at Fig. 1, station X, the vibrator when vibrating will be
checked or held up at one side of its stroke, as before mentioned, so that all the
parts at that station will be checked.
Assuming now that the apparatus at the two stations is running, and that the
arm K at station X is a little in advance of the arm at Y, so that the end of
the arm carrying the brush at X has pushed back the detent O at that station
before the trailing brush kat station Y has come upon the battery contact n¹.
Under these conditions one of the motor circuits, bor c², will be completed, as
before described, according to whether the vibrator is moving up or down, as viewed
in the drawings, and has made contact with either spring b¹ or c¹. The effect of
such a completion is to hold up the vibrator on one side and check all the apparatus
at station X to retard its motion. As the brush k at station Y comes upon the
battery-contact n¹ an impulse of electricity from main battery M B will be
transmitted through wire n², contact n¹, trailing brush, arm K, pin r, over the main
line, and at station X through the frame P, pin b, wire q, key Q, and coil of
magnet M to ground. By this impulse, therefore, the magnet M will be energized,
and attracting the armature o will draw down the spring detent O out of the path
of the end of the arm K. The spring o¹ will force the contact-plate out of contact

page_text: with the pins cb, the check or brake on the motor will be removed, and it will
start into operation to again rotate the radial arm K. At the same time the main
line circuit is completed, as described, by the plate o making contact with the
pin at station X. When this operation occurs the arms at both stations will
continue to move in their proper respective positions, that is to say, the brush k
at station Y will leave the battery contact n¹ at the moment the brush at
station X leaves the ground contact m¹. If they continue to move at the same
speed, by the time the brush end of the arm at station Y has reached the detent O
and is about to strike it, the brush k at station X will come upon the battery
contact n and an impulse of electricity will be transmitted in the manner before
described from station X to station Y to remove the detent O from the path of the
arm K. Should the arm K at station Y move more rapidly than the arm at
station X during the portion of their revolutions just described, it will strike the
detent, the parts will be thrown into the same positions as indicated at X, and the
motor at Y will be checked in the manner already described; and when the brush
at station X comes upon the battery contact n the detent will be thrown out of
the path of the arm at station Y, so that the arms at both stations can again start
together. The same operation occurs when the end k¹ of the arm at X upon its
further movement reaches or strikes the detent O, and the brush k at station Y
comes upon the battery contact n. Thus, as long as the apparatus at the two
stations is running synchronously, the detents O will be withdrawn from the paths
of the travelling arms just at the proper moment, and this will occur alternately,
two such impulses being sent from Y and two from X during each revolution of
the arm K. But should the apparatus at one station run ahead of that at the
other, the end of the arm K would strike the detent before it had been removed
by the impulse of electricity received from the distant station, and the speed of the
accelerated apparatus checked.
When the end of the arm K strikes the detent O, the detent yields and the arm
follows it for a short distance. Aside from the other results accomplished by this
movement, the yielding of the detent permits the contact finger or brush ke to move
over part of the ground contact m or m¹; and when the finger k at the other
station first comes upon the battery-contact at that station, the arm abutting
against the detent will be slightly in advance of its proper position at the moment
the impulse of electricity is transmitted to release it. This gives a period of time
for the transmitted impulses to act, and also gives an allowance for the inertia of
the arm at rest, so that by the time it commences to move it occupies the proper
relative position to the other arm. The extent of this movement may be varied by
adjusting the contact-pins c, b³, r.
During the period that the contact fingers k at each station are traversing the
circles of contacts between the ground and battery contacts, the main line is
completed from the brush at one station to the brush at the other station, and is
entirely free for any purpose for which it may be desired.
As before remarked, the ground contacts m m³, and the battery contacts n n¹ are
not immediately opposite each other, and the table of contacts is not divided into
four equal sections by these contacts. For instance, the table at station X has
24 contacts between the battery contact n and the ground contact m. There are
27 between the ground contact m and the battery contact n¹, 30 between the
battery contact n' and the ground contact m¹, and 27 between the ground
contact m¹ and the battery contact n. At station Y the four sections into which
the table is divided are proportioned in the same way, but they do not occupy the
same relative position. There are 27 contacts between n and m, 30 between m
and n, 27 between n' and m¹, and 24 between m' and n. When the arms K are
moving synchronously, however, each arm has to travel over the same number of
contacts to reach its respective ground or battery contact. This will clearly appear
by reference to the drawings. Of course the spaces between the battery and
ground contacts need not be divided in the manner illustrated, or in any particular
manner, so far as my synchronous movement is concerned. Nor do I limit myself

page_text: to the particular irregular, arrangement illustrated of the battery and ground
contacts in the circle. The irregular arrangement, in connection with the deflection
of the arms K, removes the detents at irregular intervals in the circle of rotation,
and therefore though the armis K may not start in the proper relative position,
they will in a few moments, by the alternating impulses, be brought into the
proper relation and caused to rotate synchronously.
By arranging the contacts at irregular intervals a correction can take place
oftener than once in a revolution. Should the arm be started and the contacts
placed at regular intervals, one arm might be half a revolution ahead of the other
and still both the machines would run, because the detent would be removed at the
half revolutions, but the machines would not be synchronous. If more than one
correction is to take place in a revolution the contacts should therefore be placed
at irregular intervals in the circle and the rotating arm deflected to conform to
such irregularity. Again the irregular arrangement of contacts makes the apparatus
self-synchronous when they have been started into operation.
The magnet M is shown and described as located directly in the main line
circuit, and this is perhaps as good an arrangement as any on short lines. When
_desired, however, an ordinary line relay may be used to work the magnet M
locally.
When the apparatus is running the impulses of electricity alternately sent from
one station to the other occur periodically, when the finger k comes on a battery
contact at the sending station. Such impulses always act on the detent at the
distant station to either move it out of the path of the arm K before or after said
arm comes in contact with it. The correcting checks which act on the motor that
is moving too rapidly are entirely local and occur as described when the rotating
arm K abuts against the detent O, and thus closes the shunts of the local battery
around the switch D in the motor circuits. Theoretically the rotating arms are
checked or stopped to correct the speed of the motor, but practically such checks,
when they do occur, occupy such a brief period of time that their effect on the
apparatus cannot be detected. If, therefore, telegraph instruments were connected
at each station with a number of corresponding contacts, as is contemplated in this
class of apparatus, the operators would not be aware of the correcting checks.
I have shown fifteen teeth in the ratchet wheel H' actuated by the motor, and if
the vibrator makes 30 vibrations per second, the arm K will rotate over the table
of contacts twice in a second, a speed suitable to such a table of contacts as shown.
Of course any other rate of vibration, and any other number of teeth in the ratchet
may be adopted.
Where the circle of contacts is large, or the speed of rotation rather rapid, or
where the distance from one station to the other is great, of course the width of
the ground and battery contacts may be increased so as to give a proper duration
of ground and battery connection for the effectual transmission of the impulses.
In describing the synchronous operation of my improved apparatus, started
with the assumption that the arm at each station was running. If the arms at the
two stations were at rest, with the brushes on the ground contacts m or m³, and
with the detent in the normal position indicated at Y in Fig. 1ª, then the operator
at either station could call the operator at the other, station by pushing the plate o³
of the detent back into contact with the pin b', for then a depression of the key Q
at that station would transmit an impulse of electricity froin the battery M B
through said pin, detent-plate, and frame P' over the main line to the distant
station where it would pass by way of the frame P, detent-plate, contact 7, to the
ȧrm K, its brush, and ground contact through the coil of the magnet M. to ground.
The magnet being thus energized would attract the detent armature o against its
pole and call the attention of the operator. In this way the operators may be
called up and the apparatus started whenever desired.
In starting the apparatus the arms may start in any position in which they
happen to be when the respective motors are thrown into action by the operators;
they will, however, as before remarked, by the alternate corrections, be brought

page_text: into proper position for synchronous operation, that is, into the position illustrated
in Fig. 1. Assuming for instance, that the arms start in about the positions
indicated by the full lines in Fig. 3, then they would travel until the ends ¹ of the
arms abut against the detents, as indicated by dotted lines in Fig. 3, and stop the
apparatus at both stations, as before described; then, if the operator, say at
station Y, releases the arm and throws the motor into operation by depressing the
detent, the arm at that station will commence to move in the direction of the
arrow, and when it has traveled over the table to the first battery contact n', as
shown at Y, Fig. 4, an impulse of electricity will be sent from the battery M Bat
station Y through the wire n², contact n¹, arm K, contact pin r, plate o² of the
detent, and frame P over the main line to station X, where the current passes
through the frame P, contact plate o², pin 64, and key Q through the coil of the
electro-magnet M to earth. This energizes the magnet M, and the detent O at
station X is drawn out of the path of the end of the arm K, which commences
to rotate from the positions indicated at X, Fig. 4 at the same time that the
brush k at station Y leaves the contact n². If the apparatus is running synchro-
nously now, the brush k at station X will reach the battery contact n¹ at the same
moment that the brush at station Y reaches the ground contact m¹, and, as described,
the detent will be removed from the path of the latter brush. If, however, the
arm K at Y moves ahead of the arm at X it will be stopped by the detent and the
speed of its motor checked, as has been fully explained. No matter in what
positions the arms may be started with relation to each other, the apparatus at
the stations will be alternately corrected until the arms are brought into the proper
positions shown in Fig. 1.
If the apparatus at the two stations is at rest, with the arms K pressing against
the detents so as to force them back against the pins c* b, of course the operator
at either station may release the arm at that station by depressing the detent, as
before mentioned; but if, in addition to these conditions, the vibrators of the
motors are drawn to one side so as to close either of the shunts b² c², then
the operator at either station by the depression of his key may release the motor
and apparatus at the distant station and start it into operation, as already described.
When either of the apparatus has been started it will transmit its releasing impulse
to the distant station to remove the detent from the path of the arm at that
station, and then by the alternate corrections described, the arms at both stations
will be brought into proper synchronous relation.
It will be observed that the width of the ground and battery contacts, the length
of the brush k, the deflection of the arm K, and the amount of movement of the
detent are so proportioned that the brush will come upon the ground contacts
before it moves the detent back, and will still be upon the ground contact after the
detent has been thrust entirely back. The purpose of this arrangement is that if
the arms are running synchronously, the impulse from the battery contact at one
station to the ground contact at the other will pass and energize the magnet M
before the detent has been pushed back, so that it will be removed from the path
of the arm without stopping it. This will appear clear from Figs. 1 3 and 4.
I have indicated in the simplest diagrammatic manner at each station, merely by
way of illustration, three telegraphic keys S and relays T, each connected with a
contact on the table of contacts. The relays are all preferably grounded by wire s,
through the coil of the magnet M. The front stops of the keys are connected
through a resistance Rh by wire t, with the main battery M B. I have shown
each key connected with one contact only, but of course any desired number of the
independent contacts may be connected with each set of telegraphic instruments, as
is now well understood by those expert in this matter. The operators at one
station may telegraph to the corresponding operators at the other over the inter-
rupted circuit which is given in rapid succession to each pair of operators as the
arms K synchronously rotate. The resistances Rh are introduced in the telegraph
lines for the following purpose: If the full power of the battery M B sent into
the line by the manipulation of the keys S, such telegraphic impulses would also

page_text: energize the magnet M at the distant station and might move the detent O at an
improper time. By introducing the resistances and making the detents of a
tension to resist the power of the magnets, except when energized by the full
power of the batteries M B, such an action is prevented.
The relays T are preferably grounded as shown through the magnets M, so that
in case the apparatus is not in proper position to receive the regularly transmitted
impulses sent to release the detent, as, for instance, if plate o² of detent did not
make contact with the pin 4, the operator by working the key at the distant
station may send an impulse of the full power of the battery M B through one of
the telegraphic contacts and relays at the station receiving the impulse. This
arrangement is not however deemed necessary.
It will perhaps be found best on long lines to ground the line at each end between
the contacts by inserting supplementary contacts in the circle, as is now well
understood and set forth in sundry patents.
The particular motors illustrated are, in my opinion, specially adapted to this
synchronous system. They can be adjusted so that two of them can be made to
run at speeds so nearly equal to each other that only occasional corrections of the
apparatus are required, and of course the more equality of speed the greater will be
the efficiency of the apparatus. As before remarked, this invention is not limited
to the particular motor, nor to other specific details of construction and organiza-
tion, so far as the broader principles of the invention are concerned, as electrical
engineers may readily devise other apparatus to work on the same principle.
The table of contacts shown in the drawing is larger in proportion to the size of
the motor than I prefer to construct it. The parts would be more accurately
proportioned if the vibrator of the motor were twice the length and thickness
shown, and for such a sized motor I prefer to make the vibrator about an inch in
width. This size is one which I have found to work well at the rate of thirty
vibrations per second.
As viewed in the drawings, Figs. 1 and 1º, the contacts are preferably so located
on the circular table that when it is divided into quadrants by drawing vertical
and horizontal lines through its center, such lines will pass between adjacent
contacts and not through any of them.
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 of the main 'line, independently actuated vibrators at each
end of the main line, rotating apparatus at each end of the line controlled by said
vibrators, local correcting devices at one end of the line for correcting the speed of
the vibrator and apparatus at that station solely by their own action, and means by
which a current of electricity is transmitted over the line to release or free the
vibrator and apparatus from said correcting action.
2. The combination of the main line, independently actuated vibrators at each
end of the main line, rotating apparatus at each end of the main line controlled by
said vibrators, local correcting devices at each station for correcting the speed of
either vibrator when it runs out of time with the other solely by the action of the
correcting devices at the particular station, and means by which currents of
electricity may be sent from either station to the other to release the vibrators from
said correcting action.
3. The combination of a main line, independently actuated apparatus at each
end of the main line, a vibrator at one end of the main line for controlling the
apparatus at that station, correcting devices by which the vibrator is automatically
corrected at said station solely by the action of the correcting devices at that
station when the apparatus at said station runs out of time with the apparatus at
the distant station, and means for transmitting a correcting impulse of electricity
over the line to release or free the vibrator from.said correction.
'

page_text: 4. The combination of a main line, independently rotating apparatus at each end
of the line, a vibrator at one station for actuating or controlling the apparatus at
that station, a local circuit for correcting the action of the vibrator, means by which
the rotating apparatus at the vibrator station completes said correcting circuit when
the apparatus runs out of time with the apparatus at the distant station, and means
for transmitting an impulse of electricity over the line to release the vibrator from
said correcting action when the apparatus at the two stations come into proper
relative position.
5. The combination of the main line, an independently actuated vibrator at each
end of the line, rotating apparatus controlled by said vibrators, a local circuit at
each station for correcting the speed of the vibrator, means at each station for
completing said local circuit whenever the apparatus at either station runs out of
time with that at the distant station, and means for transmitting a current of
electricity over the line to release either of said apparatus when both apparatus
come into corresponding positions.
6. The combination of a main line, a table of contacts and a rotating arm which
traverses said table at each end of the main line, a detent or circuit-changer located
in the path of said traveling arm at one station with which said arm makes contact
when it runs ahead of the other arm at the distant station, and electric devices for
transmitting a current of electricity from the distant station to separate said arm
and circuit-changer when the two apparatus come into corresponding positions, for
the purpose set forth.
7. The combination of the main line, the independently actuated apparatus at
each end of the main line, synchronously rotating devices actuated by said
apparatus, a detent or circuit-changer located in the path of said rotating apparatus
at each station, and a local circuit at each station thrown into operation by said
detent or circuit-changer to control the speed of the independently actuated apparatus
at that station.
8. The combination of the main line, independently actuated apparatus at each
end of the main line, synchronously rotating devices actuated by said apparatus, a
detent or circuit changer at each station which normally lies in the path of said
rotating devices, a local circuit at each station for controlling the independently
actuated apparatus, which circuit is thrown into operation whenever the synchro-
nously rotating devices come in contact with said detent or circuit-changer, and
electro-magnetic devices for periodically and alternately removing the detent or
circuit-changer from the path of the rotating apparatus at each station by means
of an impulse of electricity transmitted over the main line.
9. The combination of a main line, independently actuated apparatus at each end
of the main line, synchronously rotating devices actuated by said apparatus, the
circuit completer or trailing finger at each station normally connected with the main
line, a table of contacts over which said finger traverses, a detent or circuit-changer
normally located in the path of the rotating devices at each station, a local circuit
at each station controlled by said circuit-changer for correcting the speed of the
independently actuated apparatus, and the battery and ground contacts at each
station.
10. The combination of a main line, synchronously rotated apparatus at each end
of the main line, trailing fingers or circuit completers carried by said rotating
devices, a table of contacts at each station over which said circuit completers
traverse, means substantially such as described for maintaining the synchronous
rotation of said devices, and the ground and battery contacts placed at irregular
intervals in the table of contacts at each station.
11. The combination of the main line, synchronously actuated apparatus and a
table of contacts at each end of the main line, rotating arms having circuit
completers which traverse said tables of contacts actuated by said synchronously
moving apparatus, said rotating arms occupying positions when moving synchro-
nously substantially at right angles to each other, the ground and battery contacts
placed at irregular intervals in the table of contacts, and means substantially

page_text: such as described for maintaining the synchronous movement of the apparatus at
the two stations.
12. The combination of the main line, rotating apparatus at each end of the
main line, a detent in the path of the rotating apparatus at each station, and means
substantially such as described for alternately removing said detents from the paths
of the rotating apparatus to insure their equal and uniform movement.
13. The combination of the main line, rotating apparatus at each end of the main
line, a detent or circuit-changer in the path of the rotating apparatus at each
station with which either of said rotating apparatus makes contact to correct its
speed only when it runs ahead of the other apparatus, and means, substantially
such as described, for alternately removing said detent from the paths of said
rotating apparatus, substantially as set forth.
14. The combination of the main line, the rotating apparatus at each end of the
main line, a detent in the path of said rotating apparatus at each station, ground
and battery contacts at each station over which a circuit completer on the rotating
apparatus moves, and electric circuits and devices for alternately and periodically
removing said detent from the path of the rotating apparatus at each station.
15. In a synchronous system of electrical movements, substantially such as herein
described, the combination of rotating circuit completers, a table of contacts over
which said circuit completers move, and ground and battery contacts placed at
irregular intervals in said tables of contacts.
16. The combination of the main line, the independently actuated vibrator at
each end of the main line, the motor magnets, circuits, contacts, and switch devices
of each vibrator, shunts around the switch devices in the circuits of the motor
magnets, the synchronously rotating devices actuated by said vibrators, a detent
or circuit-changer located in the path of said rotating devices at each station,
contacts by means of which said circuit-changer or detent closes the shunts in the
motor circuits whenever the rotating devices at one of the stations comes in contact
with the detent, and means substantially such as described whereby the detents are
periodically alternately removed from the paths of the rotating devices.
17. In a system of synchronous movement, substantially such as herein described,
the combination of the rotating arms, the yielding detents, and the ground and
battery contacts.
18. The combination of the main line, rotating apparatus at each end of the
main line, a yielding detent in the path of the rotating apparatus at each station,
and means, substantially such as described, for alternately removing said detents
from the paths of the rotating apparatus.
19. In electrically connected rotating apparatus, the combination of the rotating
arm, and the yielding detent for acting on said arın, for the purpose set forth.
20. The combination of the main line, synchronously rotating apparatus at each
end of the main line, a detent in the path of the rotating apparatus at each station,
electro-magnets for removing said detents from the paths of said rotating apparatus,
and a key and battery at each station for transmitting an impulse of electricity to
the distant station for removing the detent from the path of the rotating apparatus.
Dated this eleventh day of August 1885.
PHILIP M. JUSTICE,
Applicant's Agent.