Improvements in Railway Signal Apparatus.
Year: 1894

page_text: και οι πρρηναιο
Complete Specification Left, 4th Dec., 1894-Accepted, 2nd Feb., 1895
TRUVIDIONAL
Improvements in Railway Signal Apparatus.
I, JOHN DANIELS TAYLOR, of Chillicothe, in the County of Ross and State of
Ohio, United States of America, Electrical Engineer, do hereby declare the nature
of this invention to be as follows:-
The object of my invention is to provide a signal which will be more plainly
visible, and will make a wider distinction between the indications of "danger" and
"safety" than is made in signals heretofore used, and which will indicate danger
with absolute certainty when danger exists. Also to provide a strong and effective
current for controlling the signal.
My invention consists in a signal having two or more radial arms, (preferably
four) attached to an axis which can be rotated, an electric motor connected with
the axis of the signal, a dynamo driven by a suitable motive power for supplying
current to the signal motors, a magnetically-operated clutch for causing one motor
to operate two signals, a relay having carbon contacts for controlling the motor
and magnets, a motor having two series of windings on the armature, one consisting
of a large number of convolutions of fine wire and another consisting of a few turns
of heavy wire, a lamp having lenses and mirrors arranged to give two separate
and distinct visual signals, and the electrical connections for connecting the
different parts in operative relation to each other, all as will be hereinafter more
fully described.
Reference is to be had to the accompanying drawings forming a part of this
Specification, in which similar letters and figures of reference indicate corresponding
parts in all the views.
Figure 1 is a rear elevation of one of the signals and its operating mechanism as
adapted for use at crossings, or for block signalings where it is desired to indicate
the condition of the track one block ahead;
Figure 2 is a vertical section through the lamp used for night signaling;
Figure 3 is a side elevation of the armature and part of the coils and commu-
tators of the track circuit generator;
Figure 4 is a side elevation, partly in section, of the signal and operating
mechanism adapted to the overlapping system of block signaling ;
Figures 5 and 6 are detail views of the clutch and lever for operating it;
Figure 7 is a diagrammatic view of the track, circuits, motors and maguets used
in operating the overlapping system; and
Figure 8 is a diagrammatic view of the track, circuits, motors and magnets used
for operating a signal block system.
In Figures 1 and 4 H, is a signal post, to the top of which is secured the
casting A, which forms a support for the motor G, and mechanism connecting it
with the signal. A shaft D is journaled in the supports m, m, and to this shaft is
secured the worm wheel E, and spider B which carries the signal arms C, C1, C³, C³.
The screw F, carried by the shaft p, connected with the armature shaft of the
motor G by the coupling 1, engages the worm wheel E. By this arrangement,
whenever the motor G is energized by the current, the worm wheel E will be slowly
When the current
rotated, thus causing the signal arms C, C1, C2, C³, to revolve.
is interrupted, the motor will stop and the signal arms will remain at rest and will
be locked in position by the screw F.
The rest of the mechanism for adapting the signal to the overlapping block

page_text: system is shown in Figures 4, 5, and 6, in which S, is one half of a clutch placed
on the shaft D, so as to be free to move longitudinally on the shaft, but prevented
from turning thereon by a feather f. projecting from the shaft into the groove in
the part S. The collar U fits loosely in the circumferential groove in the part S,
and is provided with two pins u, u, at diametrically opposite points which work in
the forked arms of the angled lever T. The chain sheave V, on the boss of which
is formed the other part of the clutch, is free to turn on the shaft D, but is
prevented from moving longitudinally thereon by a shoulder turned on the said
shaft. A shaft d is journaled in bearings a, a', secured to opposite sides of the
post H.
To one end of the said shaft d, is attached a chain sheave W, which receives the
endless chain X passing over the sheave V. To the opposite end of the shaft d is
secured a spider which carries the signal arms c, c¹, c², c³. To the side of the
post H is secured the magnet Y and stop Z. The lever T, which is journaled
between ears t on the casting A, carries on its horizontal arm an armature r, which
is supported within the field of the magnet Y. When the magnet Y is energized,
the armature is attracted towards it, thus causing the lever T to turn on its
fulcrum and move the part S of the clutch, so that it engages the part of the clutch
formed on the boss of the sheave V, so that the said sheave V rotates with the
shaft D, and transmits motion through the chain X to the sheave W, shaft d, and
signal arms c, c¹, c², c³. The screw in the stop Z is set so as to prevent any
pressure and unnecessary friction on the clutch S. When the circuit through the
magnet is broker, the spring forces back the lever T and separates the parts of
the clutch. To cause the upper set of arms to rotate it is necessary for the motor G
only to be energized. To cause the lower set of arms to rotate it is necessary for
both the motor G and magnet Y to be energized. To reduce friction of the
mechanism to a minimum, the worm wheel E is made to rotate in a body of oil
contained in a trough,k formed in the casting A.
Referring to Figure 2, L, is a lens for collecting the rays of light from the
lamp K, and throwing them out slightly divergent along the track in the direction
of the approaching train, and L', is a lens upon the opposite side of the flame
through which light passes to the mirror M, arranged at an angle of 45 degrees
with the horizon, and the said mirror reflects the light vertically downward to a
mirror Marranged at an angle of 90 degrees with the mirror M, and reflects the
light in a horizontal direction toward the approaching train through the plane
glass J.
The said plane glass J, the mirrors M, M, lenses L, L', and the lamp K, are
mounted in a casing and form a lantern which is placed at one side of the shaft D,
in such relation to the arms C, C, C, C, as to render it impossible for the said
series of arms to obscure both beams of light emerging from the lantern at one
time, in whatever position the arms may be stopped. When the signal is rotated,
the light will be seen alternately above and below the signal arms as they pas
before the lantern, and the light will appear to have a vertically reciprocating
motion, and when the signal is stationary either one or both lights will be seen
stationary. I am aware that a signal lantern has heretofore been constructed to
emit a direct beam of light and also a reflected beam of light parallel to the first
and I do not claim this broadly but only in combination with the movable semaphores
arranged to alternately eclipse these beams.
In Figure 3, P, is the armature core of the track circuit generator, N, the
commutator cylinder connected with the fine wire coils, and O, the commutator
cylinder connected with the heavy winding of the armature. The field magnet
may be of any of the well known types, and needs no illustration here. It may be
either series or shunt wound. The coils of fine and coarse wire have no connection
with each other, but they should be well insulated. The current in the heavy wire
is induced by its rotation in the magnetic field and the rotation is produced by the
current passing through the fine wire coils, the current being supplied by a dynamo
which operates the system in the manrer hereinafter described.

page_text: When the signal rotates it indicates “safety” and when the signal is stationary
it indicates "danger." At night, a light (preferably red) having an apparent
vertically-reciprocating motion, indicates safety, and either one of two red lights,
stationary, indicates danger. Each section of the track, for example, Q, Q
Figure 8, known as a block, is insulated electrically from contiguous sections by
insulating pieces i, i,, . The rails of the section Q, are connected electrically
throughout its length, and the rails of the sections Q', Q³, etc., are connected
electrically in the same manner. The dynamo g may be located at any convenient
point ou the line of the road to be protected, and the current carried to the signals
by the wires 1 and 2. The generator y sends a current through wires 1, 3, field
wires, and coils of fine wire on the armature of the motor N2, wires 4 and 2 back to
the generator g. This magnetizes the field and rotates the armature of the
motor N, thus inducing a current in the coils of heavy wire on the armature, and
if the block Q Q¹ is clear, as shown, the said current flows through the wire 5, the
rail Q, wire 6, relay R, wire 7, rail Q¹, and wire 8, back to the commutator O,
connected with the coarse wire winding of the armature. Part of this current is
wasted by conduction between the rails Q and Q through the ground and ties
when they are dry, but more especially when they are wet, and to make the
percentage of loss low, the coils of the relay R are made with very low resistance,
and a current of low potential and large quantity is used. To secure this, the
resistance of the generator must be very low. With primary batteries heretofore
used for track circuit work, this condition would be impossible to maintain on
account of the rapid consumption of the battery zines and liquids. In my system,
the current of high potential and small quantity is transformed by the motor-
transformer into one of low potential and large quantity. A high potential is
necessary in the generator 9, in order that the waste due to resistance in the wires I
and 2 may be small.
The current mentioned above flowing through the coils of the relay R, energizes
it and causes it to attract its armature and draw the armature lever y down into
contact with the stop .. This closes the circuit of the generator g, so that the
current flows through the wires 1, 9, contact, lever y, wire 10, signal-operating
motor G, wires 11 and 2, to the generator g. This energizes the motor G, causing
its armature to rotate, thus causing the signal No. 1 to revolve as before explained.
While signal No. 1 revolves it indicates that the block Q, Q', is clear, and so long
as the block is clear the signal continues to revolve.
Suppose a train to be occupying the block Q, Q³, as shewn by the wheels and
axle at e; the generator g sends a current through the wires 1, 12, the motor N³,
wires 13, and 2, back to the generator g. This rotates the armature of the said
motor, inducing a current in the secondary coils connected with the commutator O
of the said motor; but the current is prevented from reaching the relay R¹, on
account of being short circuited by the wheels and axle at e, consequently the
relay R is not energized and the lever y of the said relay is released and drawn
away from contact with the stop by a retractile spring. The circuit through
the signal-operating motor G of signal No. 2 is thus broken, the notor is not
energized, and signal No. 2 remains stationary. This condition of the said signal
indicates that the block Q, Q³, is occupied by a train or a part of a train.
Enough resistance is introduced between the commutator O and the rails to prevent
the over-heating of the armature coils when the track is occupied by a train. This
If the
is easily accomplished by using carbon brushes on the commutator ().
block QQ, is unoccupied the signal No. 3 will be rotated as just described for
signal No. 1, indicating to the train approaching at e that the block ahead
is clear.
The
The over-lapping system of block-sig aling is illustrated in Figure 7.
track circuits and insulation are exactly the same as before described in reference
to Figure 8. The current from the generator g flows through the wires 1, 3,
motor N2, wires 4 and 2, back to the generator g. This causes the armature of the
motor N2 to revolve inducing a current in the secondary coils of the motor

page_text: connected with the commutator cylinder O, and the said current flows through the
wires 5, rail Q, wires 6, relay R, wire 7, rail Q', wire 8, back to the commutator O³.
This energizes the relay R, causing the lever y to make contact with the stop x,
and close the circuit through the signal-operating motor G, so that the current
from the generator g flows through wires 1, 9, stop c, lever y, wire 10, motor G,
wires 11 and 2, back to the generator g. This energizes the motor G causing the
upper set of signal arms in signal No. 1 to revolve as before described. The rotary
motion of the upper set of arms indicates to a train approaching that signal and
moving in the direction indicated by the arrow that the block Q, Q', is clear. If
the block Q, Q³, were unoccupied, the relay R' would be energized in the manner
before described and a circuit would be formed so that a current from the
generator g would flow through the wires 1, 18, stop a¹, lover y¹, wire 30,
magnet Y, wires 31 and 2, back to the generator g; this would energize the
magnet Y, causing the clutch S to engage the clutch on the sheave V, which
would cause the lower set of arms to be rotated in the manner previously stated.
This condition of signal No. 1 would indicate that both the blocks Q, Q', and Q², Q³,
were clear; but as we suppose a train to be occupying a block Q2, Q³, at e, the
relay R¹ will not be energized and the circuit through the magnet Y will be broken
between the contact a¹ and lever y', consequently the clutch S will be disengaged
from the sheave V, and the lower set of arms of the signal No. 1 will remain
stationary. This condition of signal No. 1 indicates that the block Q, Q1, is clear
and that the block Q3, Q³, is occupied.
The circuit through the motor G of signal No. 2 will also be broken between the
contacts and y', as before described, and the.motor G will not be energized,
consequently both the upper and lower sets of arms of signal No. 2 will remain
stationary whether the magnet Y' is in circuit or not. This condition of signal
No. 2 indicates that the block Q2, Q³, immediately ahead is occupied.
If the block Q, Q, be clear the relay R2 of signal No. 3 will be energized as
before described and the lever y² will make contact with the contact 2 thereby
closing two circuits for the current from the generator g, one through the
wires 1, 23, stop ², lever y², wire 24, and motor G, of signal No. 3, the wires 25
and 2 back to the generator, and the other through the wires 1, 23, stop.², lever y²,
wire 32, magnet Y¹, wires 33 and 2, back to the generator. The current passing
through the circuit first described energizes the motor G of signal No. 3 and
rotates the upper set of arms of the said signal, and if the magnet Y2 be energized
it causes the lower set to be rotated also.
The current passing over the second circuit described energizes the magnet Y₁
but has no effect on signal No. 2, so long as the motor G¹ of that signal is not
running. As the train indicated at passes the insulating pieces, the first
pair of wheels that touch the rails Q, Q, short circuits the relay R and breaks
hoth the circuits named above. This stops the motion of both sets of arms on
signal No. 3, and disengages the clutch on signal No. 2. After the last pair of
wheels leaves the rails Q, Q, the current is restored through the relay R', and
by means of the relay through the motor G of signal No. 2, and the magnet Y of
signal No. 1, as before described. This causes the upper set of arms on signal No. 2
to be rotated and the clutch on signal No. 1 to be engaged causing the lower set of
arms to rotate in conjunction with the upper set.
The relay R is provided with carbon contacts as they will not oxidize nor fuse
and stick together. The signals are intended to be placed with the plane of the
arms and of rotation at right angles to the track. In Figures 7 and 8 they are
shewn parallel with the track to facilitate shewing them on the drawings.
The signal-operating motor G should be series wound the field magnet having
about double the number of turns of wire usually put on a series motor of the
same size in order that the speed may be slow.
To describe my method of distribution I will suppose the signals in use on
portion of double track road ten miles long. I would locate the generating
Station containing the generator g and an engine for driving it as near the middle

page_text: of the portion of road to be blocked as possible in order to save wire. The main
wires 1 and 2 would be connected to the terminals of the dynamo and would extend
each as far as the system of blocks extend. For a line of this length 1 would use
a dynamo having an electromotive force of 110 to 125 volts and a No. 8 copper
wire could be used for the main wires. On the east bound track the secondary
coils of the transformers N1, N2, etc., would be connected to the rails at the east
end of the sections or blocks and the relays R, R1, R2, etc, would be connected to
the west ends of the blocks. On the west bound track this order of course would
be reversed but it is only necessary to describe the operations on one track. The
primary coils and field coils of the rotary transformers would be connected with
the main wires 1 and 2 at the nearest point to the transformer. The motors G, G',
etc., would be connected to the main wires 1 and 2 through the contact points of
the relays R, R', etc. The transformers and signal motors would be connected to
the main wires 1 and 2 in parallel. The transformers would always be in circuit
and would run continuously but the signal motors G would only be in circuit when
the contacts of the corresponding relays were closed. The secondary coils of the
transformers consist of such a number of turns of wire that an electrom tive force
of 2 or 3 volts will be induced in them by their rotation in the magnetic field of
the transformer field magnets, and the wire in the coils is of such a size that it will
carry ten or fifteen amperes of current without over-heating. Coils of this
description would have a very low resistance and the difference of potential at the
terminals will be almost constant, that is no matter how many paths are accorded
the current each one will get as much current as though it were only one.
objects of this arrangement is to keep the current through the relay R as nearly
constant as possible, so that when more paths are offered to the current as when
the ground is wet, the relay will still get as much current as it would if the ground
were dry. This is not perfectly attained because if the potential were absolutely
constant, when the secondary coils are short circuited by a train the resistance of
which is almost nothing, the current would be almost infinite and either primary or
secondary coils would be fused. In order to prevent this, just enough resistance
is introduced in circuit with the secondary coils to keep the current within the safe
limits of 10 or 15 amperes.
But the object is much more nearly attained in my
method of using transformers than by the old method of using gravity batteries
the current from which on short circuit will not exceed ampere and the amount
circulating in the coils of the relay would not exceed 2 ampere while by my
method I can easily get one ampere through the relay R. The current induced in
the secondary coils of the transformer flows through the rails and through the
relay at the other end of the block. This energizes the relay and causes it to
close the circuit through the signal motor G. The current which actuates the
motor G comes direct from the dynamo g through the wires 1 and 2.
Dated this outh dow of Mouch 1004
20
The
J. D. TAYLOR,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.
COMPLETE SPECIFICATION.
Improvements in Railway Signal Apparatus.
I, JOHN DANIELS TAYLOR, of Chillicothe, in the County of Ross, and State
of Ohio, United States of America, Electrical Engineer, do hereby declare the
nature of this invention, and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement :-
The object of my invention is to provide a signal which will be more plainly
visible, and will make a wider distinction between the indications of "
danger" and

page_text: "safety
than is made in signals heretofore used, and which will indicate danger
with absolute certainty when danger exists. Also to provide a strong and effective
current for controlling the signal.
My invention consists in a signal having two or more radial arms, (preferably
four) attached to an axis which can be rotated, an electric motor connected with
the axis of the signal, a dynamo driven by a suitable motive power for supplying
current to the signal motors, a magnetically-operated clutch for causing one motor
to operate two signals, a relay having carbon contacts for controlling the motor
and magnets, a motor having two series of windings on the armature, one consisting
of a large number of convolutions of fine wire and another consisting of a few
turns of heavy wire, a lamp having lenses and mirrors arranged to give two
separate and distinct visual signals, and the electrical connections for connecting
the different parts in operative relation to each other, all as will be hereinafter
more fully described.
Reference is to be had to the drawings filed with my Provisional Specification,
in which similar letters and figures of reference indicate corresponding parts in all
the views.
Figure 1 is a rear elevation of one of the signals and its operating mechanism as
adapted for use at crossings, or for block signalings where it is desired to indicate
the condition of the track one block ahead ;
Figure 2 is a vertical section through the lamp used for night signaling;
Figure 3 is a side elevation of the armature and part of the coils and commutators
of the track circuit generator;
Figure 4 is a side elevation, partly in section, of the signal and operating
.mechanism adapted to the overlapping system of block signaling;
Figures 5 and 6 are detail views of the clutch and lever for operating it;
Figure 7 is a diagrammatic view of the track, circuits, motors and magnets used
in operating the over-lapping system; and
Figure 8 is a diagrammatic view of the track, circuits, motors and magnets used
for operating a single block system.
In Figures 1 and 4, II, is a signal post, to the top of which is secured the
casting A, which forms a support for the motor G, and mechanism connecting it
with the signal. A shaft D, is journaled in the supports m, m, and to this shaft is
secured the worm wheel E, and spider B which carries the signal arms C, C1, C2, C³.
The screw F, carried by the shaft P, connected with the armature shaft of the
motor G by the coupling I, engages the worm wheel E. By this arrangement,
whenever the motor G is energized by the current, the worm wheel E will be
When the
slowly rotated, thus causing the signal arms C, (", ", ("" to revolve.
current is interrupted, the motor will stop and the signal arms will remain at rest
and will be locked in position by the screw F.
The rest of the mechanism for adapting the signal to the overlapping block
system is shown in Figures 4, 5 and 6, in which S, is one half of a clutch placed
on the shaft D, so as to be free to move longitudinally on the shaft, but prevented
from turning thereon by a feather f, projecting from the shaft into the groove in
the part S. The collar U fits loosely in the circumferential groove in the part S,
and is provided with two pins u, u, at diametrically opposite points, which work in
the forked arms of the angled lever T. The chain sheave V, on the boss of
which is formed the other part of the clutch, is free to turn on the shaft D, but is
prevented from moving longitudinally thereon by a shoulder turned on the said
shaft. A shaft d is journaled in bearings a, a¹, secured to opposite sides of the
post H.
b
To one end of the said shaft d, is attached a chain sheave W, which receives the
endless chain X passing over the sheave V. To the opposite end of the shaft d is
secured a spider which carries the signal arms c, e¹, c², . To the side of the
post H is secured the magnet Y and stop Z. The lever T, which is journaled
between ears t on the casting A, carries on its horizontal arm an armature r, which
is supported within the field of the magnet Y. When the magnet Y is energized,

page_text: the armaturer is attracted towards it, thus causing the lever T to turn on its
fulcrum and move the part S of the clutch, so that it engages the part of the
clutch formed on the boss of the sheave V, so that the said sheave V rotates with
the shaft D, and transmits motion through the chain X to the sheave W, shaft d
and signal arms c, c', c², c³. The screw in the stop Z is set so as to prevent any
pressure and unnecessary friction on the clutch S. When the circuit through the
magnet Y is broken, the spring forces back the lever T and separates the parts
of the clutch. To cause the upper set of arms to rotate it is necessary for the
motor G only to be energized. To cause the lower set of arms to rotate it is
necessary for both the motor G and magnet Y to be energized. To reduce friction
of the mechanism to a minimum, the worm wheel E is made to rotate in a body of
oil contained in a trough k formed in the casting A.
Referring to Figure 2, L, is a lens for collecting the rays of light from the
lamp K, and throwing them out slightly divergent along the track in the direction
of the approaching train, and L', is a lens upon the opposite side of the flame
through which light passes to the mirror M, arranged at an angle of 45° with the
horizon, and the said mirror reflects the light vertically downward to a mirror M
arranged at an angle of 90° with the mirror M, which reflects the light in a
horizontal direction toward the approaching train through the plane glass J.
The said plane glass J, the mirrors M', M, lenses L, L', and the lamp K, are
mounted in a casing and form a lantern which is placed at one side of the shaft D,
in such relation to the arms C, C¹, C³, C³, as to render it impossible for the said
series of arms to obscure both beams of light emerging from the lantern at
one time, in whatever position the arms may be stopped. When the signal
is rotated, the light will be seen alternately above and below the signal arms
as they pass before the lantern, and the light will appear to have a vertical
reciprocating motion, and when the signal is stationary either one
lights will be seen stationary. I am aware that a signal lantern has been
heretofore constructed to emit a direct beam of light and also a reflected
beam of light parallel to the first and I do not claim this broadly but only
in combination with the movable semaphores arranged to alternately eclipse these
beams.
or both
In Figure 3, P, is the armature core of the track circuit generator, N, the
commutator cylinder connected with the fine wire coils, and O, the commutator
cylinder connected with the heavy winding of the armature. The field magnet
may be of any of the well known types, and needs no illustration here. It
may be either series or shunt wound. The coils of fine and coarse wire have
no connection with each other, but they should be well insulated. The current
in the heavy wire is induced by its rotation in the magnetic field and the
rotation is produced by the current passing through the fine wire coils, the
current being supplied by a dynamo which operates the system in the manner
hereinafter described.
When the signal rotates it indicates "safety," and when the signal is stationary
it indicates "danger." At night, a light (preferably red) having an apparent.
vertically-reciprocating motion, indicates safety, and either one of two red lights,
stationary, indicate danger. Each section of the track, for example, Q, Q',
Figure 8, known as a block, is insulated electrically from contiguous sections by
insulating pieces i, 1, 2, . The rails of the section Q, are connected electrically
throughout its length, and the rails of the sections Q1, Q2, etc., are connected
electrically in the same manner. The dynamo g may be located at any convenient
point on the line of the road to be protected, and the current carried to the
signals by the wires 1 and 2. The generator g sends a current through wires 1, 3,
field wires, and coils of fine wire on the armature of the motor N2, wires 4 and 2
back to the generator g. This magnetizes the field and rotates the armature
of the motor N2, thus inducing a current in the coils of heavy wire on the
armature, and if the block Q Qis clear, as shown, the said current flows through
the wire 5, the rail Q, wire 6, relay R, wire 7, rail Q' and wire 8, back to

page_text: Part
the commutator O, connected with the coarse wire winding of the armature.
of this current is wasted by conduction between the rails Q and Q1 through
the ground and sleepers when they are dry, but more especially when they
are wet, and to make the percentage of loss low, the coils of the relay R
are made with very low resistance, and a current of low potential and large
quantity is used. To secure this, the resistance of the generator must be very
low. With primary batteries heretofore used for track circuit work, this condition
would be impossible to maintain on account of the rapid consumption of the
battery zincs and liquids. In my system, the current of high potential and
small quantity is transformed by the motor-transformer into one of low potential
and large quantity. A high potential is necessary in the generator g, in order that
the waste due to resistance in the wires 1 and 2 may be small.
The current mentioned above flowing through the coils of the relay R, energizes
it and causes it to attract its armature and draw the armature lever y down
into contact with the stop a. This closes the circuit of the generator g, so that
the current flows through the wires 1, 9, contact x, lever y, wire 10, signal
operating motor G, wires 11 and 2, to the generator g. This energizes the
motor G, causing its armature to rotate, thus causing the signal No. 1 to
revolve as before explained. While signal No. 1 revolves, it indicates that the
block QQ is clear, and so long as the block is clear the signal continues to
revolve.
Suppose a train to be occupying the block Q2, Q³, as shown by the wheels and
axle at e; the generator 9 sends a current through the wires 1, 12, the motor N³,
wires 13 and 2 back to the generator g. This rotates the armature of the said
motor, inducing a current in the secondary coils connected with the commutator ()
of the said motor; but the current is prevented from reaching the relay R', on
account of being short circuited by the wheels and axle at e, consequently the
relay R is not energized, and the lever y₁ of the said relay is released and
drawn away from contact with the stop 1, by a retractile spring. The circuit
through the signal-operating motor G of signal No. 2 is thus broken, the
motor is not energized, and signal No. 2 remains stationary. This condition
of the said signal indicates that the block Q2 Q' is occupied by a train or a
part of a train. Enough resistance is introduced between the commutator (
and the rails to prevent the over-heating of the armature coils when the track
is occupied by a train. This is easily accomplished by using carbon brushes
on the commutator O. If the block QQ is unoccupied, the signal No. 3
will be rotated as just described for signal No. 1, indicating to the train
approaching at that the block ahead is clear.
The over-lapping system of block signaling is illustrated in Figure 7. The
track circuits and insulation are exactly the same as before described in reference
to Figure 8. The current from the generator g flows through the wires 1, 3,
motor N³, wires 4 and 2 back to the generator g. This causes the armature of the
motor No to revolve, inducing a current in the secondary coils of the motor
connected with the commutator cylinder O, and the said current flows through the
wires 5, rail Q, wires 6, relay R, wire 7, rail Q', wire 8, back to the
commutator O. This energizes the relay R, causing the lever y to make
contact with the stop r, and close the circuit through the signal-operating
motor G, so that the current from the generator 9 flows through wires 1, 9,
stop x, lever y, wire 10, motor G, wires 11 and 2 back to the generator g.
This energizes the motor G, causing the upper set of signal arms in signal No. 1
to revolve as before described. The rotary motion of the upper set of arms
indicates to a train approaching that signal and moving in the direction indicated
by the arrow that the block QQ' is clear. If the block Q Q were unoccupied,
the relay R' would be energized in the manner before described, and a circuit
would be formed so that a current from the generator g, would flow through
the wires 1, 18, stop ', lever ', wire 30, magnet Y, wires 31 and 2 back to
the generator g; this would energize the magnet Y, causing the clutch S to

page_text: engage the clutch on the sheave V, which would cause the lower set of arms
to be rotated in the manner previously stated. This condition of signal No. 1
would indicate that both the blocks QQ' and Q Q were clear; but as we
suppose a train to be occupying a block Q3 Q3 at e, the relay R¹ will not be
energized and the circuit through the magnet Y will be broken between the
contact and lever y', consequently the clutch S will be disengaged from the
sheave V. and the lower set of arms of the signal No. 1 will remain stationary.
This condition of signal No. 1 indicates that the block QQ is clear, and that the
block Q2 Q3 is occupied.
The circuit through the motor G of signal No. 2 will also be broken between
the contacts and y' as before described, and the motor G will not be energized,
consequently both the upper and lower sets of arms of signal No. 2 will remain
stationary whether the magnet Y' is in circuit or not. This condition of
signal No. 2 indicates that the block Q2 Q3 immediately ahead is occupied.
If the block Q Q be clear, the relay R² of signal No. 3 will be energized as
before described, and the lever y² will make contact with the contact, thereby
closing two circuits for the current from the generator g, one through the
wires 1, 23, stop, lever y², wire 24 and motor G of signal No. 3, the
wires 25 and 2, back to the generator, and the other through the wires 1, 23,
stop, lever y², wire 32, magnet Y', wires 33 and 2 back to the generator.
The current passing through the circuit first described energizes the motor G
of signal No. 3, and rotates the upper set of arms of the said signal, and if
the magnet Y2 be energized, it causes the lower set to be rotated also.
The current passing over the second circuit described energizes the magnet Y',
but has no effect on signal No. 2, so long as the motor G of that signal is
not running. As the train indicated at e passes the insulating pieces it is, the first
pair of wheels that touch the rails QQ, short circuits the relay R2 and breaks
both the circuits named above. This stops the motion of both sets of arms
on signal No. 3, aud disengages the clutch on signal No. 2. After the last pair of
wheels leaves the rails QQ³, the current is restored through the relay R',
and by means of the relay, through the motor G of signal No. 2 and the
magnet Y of signal No. 1, as before described. This causes the upper set
of arms on signal No. 2 to be rotated, and the clutch on signal No. 1 to
be engaged, causing the lower set of arms to rotate in conjunction with the
upper set.
The relay R is provided with carbon contacts as they will not oxidize nor fuse
and stick together. The signals are intended to be placed with the plane of the
arms and of rotation at right angles to the track. In Figures 7 and 8 they are
shown parallel with the track to facilitate showing them on the drawings.
The signal operating motor G should be series wound, the field magnet having
about double the number of turns of wire usually put on a series motor of the
same size in order that the speed may be slow.
To describe my method of distribution, I will suppose the signals in use on a
portion of double track road ten miles long. I would locate the generating station
containing the generator g and an engine for driving it as near the middle of the
portion of road to be blocked as possible, in order to save wire. The main wires 1
and 2 would be connected to the terminals of the dynamo and would extend each
as far as the system of blocks extend. For a line of this length I would use a
dynamo having an electromotive force of 110 to 125 volts and a No. 8 copper wire
could be used for the main wires. On the east bound track the secondary coils
of the transformers N¹, N, etc., would be connected to the rails at the east end of
the sections or blocks and the relays R, R1, R2, etc., would be connected to the
west ends of the blocks. On the west bound track this order of course would be
reversed but it is only necessary to describe the operations on one track.
primary coils and field coils of the rotary transformers would be connected with
the main wires 1 and 2 at the nearest point to the transformer. The motors G,
would be connected to the main wires 1 and 2 through the contact points of the
B
The

page_text: relays R, R', etc. The transformers and signal motors would be connected to the
main wires 1 and 2 in parallel. The transformers would always be in circuit and
would run continuously but the signal motors G, would only be in circuit when the
contacts of the corresponding relays were closed. The secondary coils of the
transformers consist of such a number of turns of wire that an electromotive force
of two or three volts will be induced in them by their rotation in the magnetic
field of the transformer field magnets, and the wire in the coils is of such a size
that it will carry 10 or 15 amperes of current without overheating. Coils of this
description would have a very low resistance and the difference of potential at the
terminals would be almost constant, that is, no matter how many paths are afforded
the current, each one would get as much current as though it were the only one.
The object of this arrangement is to keep the current through the relay R as
nearly constant as possible, so that when more paths are offered the current, as
when the ground is wet, the relay will still get as much current as it would if the
ground were dry. This is not perfectly attained because if the potential were
absolutely constant, when the secondary coils are short circuited by a train the
resistance of which is almost nothing, the current would be almost infinite and
either primary or secondary coils would be fused. In order to prevent this just
enough resistance is introduced in circuit with the secondary coils to keep the
current within the safe limits of 10 or 15 amperes. But the object is much more
nearly attained in my method of using transformers than by the old method of
using gravity batteries the current from which on short circuit will not exceed
tampere and the amount circulating in the coils of the relay would not exceed
ampere while by my method I can easily get one ampere through the relay R.
The current induced in the secondary coils of the transformer flows through the
rails and through the relay at the other end of the block. This energizes the
relay and causes it to close the circuit through the signal motor G. The current
which actuates the motor G comes direct from the dynamo g through the wires 1
and 2.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is,―
1. The herein-described method of signaling, which consists in displaying
a slowly moving signal for safety, and a fixed signal for danger, as herein
specified.
2. In electric signal-operating mechanism, a high potential generator adapted
to furnish a current to a series of blocks, transformers for transforming the high
potential current at each signal to one of lower potential, the low potential
current formed of the track rails and wheels and axles of the train, and
connecting wires, and the controlling relay located at the preceding station,
substantially as specified.
3. In a block signal system, the combination of a railway track formed of
sections insulated from each other, and an inter-communicating series of revolving
signals constructed to revolve for safety signals, and to remain stationary for
danger signals, substantially as specified.
4. In a block signal system for railways, the combination of a railway track
formed of sections insulated from each other, an inter-communicating series of
electrical signals, a high potential generator for supplying the series with
current, and series of transformers for transforming the high potential supply
current to a current of low potential, for use in the track circuit, substantially as
specified.
5. In a block signal system for railways, the combination, with a revoluble
signal, of a source of light yielding two light beams, the said revoluble signal
being arranged to eclipse the light beams in alternation, substantially as specified.
6. In a block signal system, the combination of a revoluble signal, an
electric motor connected with the signal, an auxiliary revoluble signal connected

page_text: mechanically with the motor-driven signal, and electro-magnetically-operated
clutch mechanism for connecting and disconnecting the auxiliary signal, substan-
tially as specified.
7. In a block signal, the combination of the primary circuit, the transformer
and secondary circuit, the track circuit taking the current from the secondary
circuit of the motor-transformer at one signal, the relay placed in the track
circuit at the preceding signal, the signal-operating motor controlled by the relay,
and the revolving signal operated by the motor, substantially as specified.
8. The combination, in an overlapping signal, of the motor G, shaft D,
arms C, C1, C2, C3, the shaft d, the arms c, c¹, c³, c³, sheaves V, W, chain X,
clutch S, lever T, and the magnet Y, substantially as specified.
9. In a block signal system, the combination, with the moving signals, of a lamp
constructed to emit two parallel alternating beams in the same direction,
substantially as specified.
10. In a block signal system, the combination, with the revolving signal provided
with light eclipsing arms, of the lamp K, the lenses L, L', and the reflectors M, M',
substantially as specified.
11. In a block signal, the combination, with the primary and secondary circuits,
of a relay provided with separable carbon contact points for the prevention of the
permanent closure of the circuit by sticking, substantially as specified.
Dated this 3rd day of December 1894.
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.