IMPROVEMENTS IN AND RELATING TO INDICATING APPARATUS OR SIGNALS FOR RAILWAY SWITCHES OR POINTS
Year: 1881

page_text: "
LETTERS PATENT to William Phillips Thompson, of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool, in the County of Lancaster, and
323, High Holborn, in the County of Middlesex, Civil Engineer, for an Inven-
tion of IMPROVEMENTS IN AND RELATING TO INDICATING APPARATUS OR
SIGNALS FOR RAILWAY SWITCHES OR POINTS." A communication from abroad
by Wesley Ward Gary, of Boston, in the County of Suffolk, in the State of
Massachusetts, United States of America.
PROVISIONAL SPECIFICATION left by the said William Phillips Thompson
at the Office of the Commissioners of Patents on the 21st September 1881.
WILLIAM PHILLIPS THOMPSON, of the Agency for Foreign Patent Solicitors,
6, Lord Street, Liverpool, in the County of Lancaster, and 323, High Holborn,
in the County of Middlesex, Civil Engineer. "IMPROVEMENTS IN AND RELATING
TO INDICATING APPARATUS OR SIGNALS FOR RAILWAY SWITCHES OR POINTS."
A communication from abroad by Wesley Ward Gary, of Boston, in the County
of Suffolk, in the State of Massachusetts, United States of America.
The object of this Invention is to produce an automatic signal for railways to be
operated by a magneto generator, and without batteries, for the purpose of indi-
cating to moving trains whether a still distant switch is open or closed.
To this end the Invention consists more particularly in the combination of a
magneto generator to be operated by passing trains, a signal operated by said
generator, and a circuit closing device connected with the switch or switch
operating mechanism in such manner that the circuit will be opened and closed
by the act of opening and closing the switch.
This Invention is susceptible of embodyment in various forms of apparatus
which will readily suggest themselves to the skilled mechanic, and all of which
will operate upon substantially the same principle.
In carrying out this Invention it is preferable to make use of a signal which
stands normally in a position indicating danger, to mount this on a circuit which
embraces the magneto machine operated by the train and the circuit breaking
device operated by the switch.

page_text: Under the above arrangement the circuit is in a closed condition whenever the
switch is closed and the main track unbroken, and at the same time the signal
stands in the position indicating danger.
While the parts are in this condition a train approaching the switch will, while
still distant therefrom, actuate the generator, from which a current will be trans-
mitted through the circuit to the signaling instrument, causing said instrument to
move from the position indicating danger to that indicating safety, thus informing
the engineer that the switch is closed. If however the switch is open it will effect
the breaking of the circuit, and the result will be that although the approaching
train operates the magneto-generator as before, the break in the circuit will prevent
the current from operating the signal, and consequently the signal will remain in
its normal position indicating danger, thus informing the engineer that the still
distant switch is in an open position.
It will be seen that the basis of the Invention consists mainly in the combi-
nation of the circuit breaking devices with the switch, the magneto generator, and
the signal standing normally in the position which indicates danger.
This system of signaling is specially advantageous in that it not only serves to
show when the switch is open and when it is closed, but also in that it warns the
engineer or other observer of any breakage which may be caused accidentally or
maliciously in the circuit, thus calling attention to a breakage in the line, and
preventing unscrupulous persons from tampering with or preventing the action of
the apparatus. Under this system it becomes impossible for the switch to remain
open or for the line to remain broken without warning to the engineer or other
observer.
This Invention comprises the following parts:-The main track or railway, the
side or switch track, the switch rails or switch proper, these rails being connected
as usual by a rod to an upright rock shaft provided with a hand lever, a half
rotation by means of the hand lever serving to open or close the switch, the main
circuit wires extending by the side of the railway track from the switch operating
device to a point at any desired distance therefrom and connected with the
signaling instrument, and a magneto-generator which will be ordinarily be near each
other, but at a considerable distance from the switch. A circuit closing device
consisting of two spring arms mounted in such position that they will be acted
upon and forced together to close the circuit by means of the crank shaft which
operates the switch, the arrangement being such that the circuit will be closed and
remain closed while the switch is closed, but be opened and permitted to remain
open whenever the switch is open.
The signaling instrument in the present instrument consists of a vibrating arm
operated by means of an electro magnet, and arranged to present different colored
glasses or shades in front of a lantern as it is moved to and fro.
It consists of an upright post or support surmounted by a lamp, an upright
vibratory arm, the upper end of which is provided with two different coloured
glasses, one or the other of which will be presented in front of the light according
to the position in which the arm stands. At its lower end the arm is provided
with an electro magnet mounted in the main circuit. This electro magnet is
arranged in front of, and its core serves as an armature to a permanent magnet
which will have its poles reversed in relation to those of the electro magnet. A
spiral spring connected with the lever serves to draw the electro magnet away
from the permanent magnet, and to hold it in that position during the time that
there is no current flowing in the circuit.
During the time that the arm is in this position, which is its normal position,
the signal at its upper end is in position to indicate danger. Whenever a current
passes through the main circuit the electro magnet becomes incited, and is attracted
towards the permanent magnet, thereby moving the lever and causing the signal
to change from the position indicating danger to that indicating safety.
Passing next to the magneto generator, it consists in the present instance of a
permanent magnet and an electro magnet or induction coil, the latter mounted in

page_text: the main circuit and arranged to vibrate or reciprocate in relation to the permanent
magnet. The electro magnet is mounted upon a horizontal swinging arm, and is
actuated by means of an upright arm on one end of a horizontal rock shaft, the
opposite end of which is provided with an arm or treadle arranged by the side of
the railway track in position to be depressed by the wheels of the passing cars.
The operation of the apparatus is as follows:-
The switch being open, the circuit breaking devices are released from the switch
operating crank, and the circuit remains broken. If now a train approaches the
switch it will act upon the lever, and cause the operation of the magneto generator,
producing an electric current; but as the circuit is broken this current will have no
effect, and the signal will remain in its normal position indicating danger, thus
warning the engineer that the switch stands in an open position, or that the circuit
has been otherwise broken, in either of which cases will immediately arrest the
motion of the train.
If however the switch be closed, the switch operating crank bearing against the
circuit closing device will maintain the continuity of the circuit. A train
approaching the track whilst the parts are in this condition will operate the
magneto generator, and thereby transmit an electro current through the circuit to
the signaling instrument. The effect of the current will be to excite the electro
magnet, which will immediately move the lever, and thereby cause the signal to
indicate the condition of safety, from which the engineer will understand that the
switch is in a closed position and the signal in an operative condition.
It will of course be understood that in order to have the signal remain in the
position indicating safety, the generator will be provided with an ordinary com-
mutator, whereby the current is caused to act continuously to hold the signal in
the position indicating safety. The apparatus may be operated without the
commutator; but as there would then be a repeated vibration of the arm or lever,
the use of the commutator is preferred. As soon as the train has passed the
generator, or shortly afterwards, the electric current will terminate and the signal
will at once fall back to the position indicating danger.
While the vibratory generator answers a good purpose it is preferred to make
use in ordinary cases of a rotary magneto generator, constructed in any of the
ordinary known forms, and provided preferably with a commutator.
The rotary generator may receive motion through any suitable devices arranged
to be actuated by passing trains. Either of the forms of apparatus represented in
United States Letters Patent, No. 240,694, 240,695, 240,606, or that represented
in the application filed April 21, 1881, will answer a good purpose in this
connection.
In place of the peculiar form of signal represented any other known or suitable
form of electro-magnetic either audible or visual may be used, provided the signal
stands normally in the position indicating danger.
In place of the switch-operating crank and the fingers for effecting the opening
and closing of the circuit, any other suitable device having a similar mode of
operation may be used, the only essential requirement in this regard being that
the opening and closing of the switch shall open and close the circuit; or with
a switch may be used a magneto-electric generator and a signal or indicator
in such manner that the movement of the switch will cause the generator
to actuate the signal or indicator. The essence of the Invention consists in
the combination of the magneto-generator with the switch, and the details of
the apparatus may be modified to any extent desired. The form of the generator,
whether of a rotary, vibratory, or other type, the same manner of its connection
with the switch, and the form of the signaling instrument employed, are all matters
of secondary importance, susceptible of many changes which will be required in
different cases and under different circumstances, and which will readily suggest
themselves to the skilled mechanic according to the circumstances of the
situation.
When the switch is being opened the crank of shaft strikes the arm of the

page_text: permanent magnet and moves the armature backward from the magnet, thereby
inducing an electric current or impulse through the coil of the armature, and in
like manner as the shaft is turned to close the switch, the armature is permitted to
move towards the magnet, thereby inducing another current or impulse, which
however differs in polarity from that produced in opening the switch. The
currents thus produced are transmitted by wires or other conductors to a distant
point by the side of the track, and there applied to operate a signal or indicator.
The signal or indicator consists of two permanent magnets bearing reversed poles
opposite each other, and an intermediate vibratory armature coiled with insulated
wire which is connected with the main circuit. The armature is connected to the
lower end of a lever, the upper end of which is provided with a target or signal
arranged to be thrown into and out of a fixed casing by the motion of the lever.
When the switch stands closed and the main track unbroken the target stands
within the casing and is concealed. The act of opening the switch causes tho
generator to operate, thereby producing an electric current which is transmitted
over conductors to the distant signal, where it causes the polarization of the
vibratory armature which is immediately attracted to one magnet and repelled
from the other, thereby moving a lever and throwing the signal outward, exposing
it to view, and thereby giving notice to approaching trains that the switch is
open. The signal stands in this position as long as the switch remains open.
In the act of closing the switch, the movement of the armature in the generator
again causes the polarization of the armature in the signal, giving the same
however the reverse polarity, and causing the same to be moved in the opposite
direction so as to conceal the signal. Any other suitable form of signal actuated
or controlled by means of an electro-magnet may be employed, and in some cases
a magneto-bell will be used in addition thereto or in place thereof to give audible
notice whenever the switch is moved. When required by the construction of the
signaling instrument, the generator may be provided with a commutator as usual
in this class of instrument. The generator may be connected with any moving part
of the switch or switch-operating devices either directly or through intermediate
gearing. The permanent magnet magnet or magnets may be moved instead of the
armature whenever it is found more convenient so to do. When a rotary generator
is employed it may have a pinion driven directly from a large gear wheel secured
to the vertical crank shaft.
In order to secure the better and easier action of the vibrator signal, there may
be applied to the vibratory armature two springs extending in opposite directions,
and so arranged that they stand in equilibrium or free from strain when the
armature is midway between the magnets. Being thus arranged they are
strained alternately as the armature moves to and fro. These springs answer the
same purpose when a bell striker is attached to the armature.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Phillips Thompson in the Great Seal Patent Office on the
21st March 1882.
WILLIAM PHILLIPS THOMPSON, of the Agency for Foreign Patent Solicitors,
6, Lord Street, Liverpool, in the County of Lancaster, and 323, High Holborn, in
the County of Middlesex, Civil Engineer. "IMPROVEMENTS IN AND RELATING TO
INDICATING APPARATUS OR SIGNALS FOR RAILWAY SWITCHES OR POINTS." A
communication from abroad by Wesley Ward Gary, of Boston, in the County of
Suffolk, in the State of Massachusetts, United States of America.
The object of this Invention is to produce an automatic signal for railways to
be operated by a magneto-generator and without batteries, for the purpose of
indicating to moving trains whether a still distant switch is open or closed.
To this end the Invention consists more particularly in the combination of a
magneto-generator to be operated by passing trains, a signal operated by said
generator, and a circuit closing device connected with the switch or switch-operating
mechanism in such manner that the circuit will be opened and closed by the act of
opening and closing the switch.
This Invention is susceptible of embodiment in various forms of apparatus which
will readily suggest themselves to the skilled mechanic after a reading of this
Specification, and all of which will operate upon substantially the same principle.
In carrying out this Invention it is preferable to make use of a signal which
stands normally in a position indicating danger, to mount this on a circuit which
embraces the magneto machine operated by the train and the circuit-breaking
device operated by the switch. Under the above arrangement the circuit is in a
closed condition whenever the switch is closed and the main track unbroken, and
at the same time the signal stands in the position indicating danger. While the
parts are in this condition a train approaching the switch will, while still distant
therefrom, actuate the generator, from which a current will be transmitted through
the circuit to the signaling instrument, causing said instrument to move from the
position indicating danger to that indicating safety, thus informing the engineer
that the switch is closed. If however the switch is open it will effect the breaking
of the circuit, and the result will be, that although the approaching train operates
the magneto-generator as before, the break in the circuit will prevent the current
from operating the signal and consequently the signal will remain in its norinal
position indicating danger, thus informing the engineer that the still distant switch
is in an open position.
It will be seen that the basis of the Invention consists mainly in the combination
of the circuit-breaking devices with the switch, the magneto-generator, and the
signal standing normally in the position which indicates danger.
This system of signaling is specially advantageous in that it not only serves to
show when the switch is open and when it is closed, but also in that it warns the
engineer or other observer of any breakage which may be caused accidentally or
maliciously in the circuit, thus calling attention to a breakage in the line and
preventing unscrupulous persons from tampering with or preventing the action
of the apparatus. Under this system it becomes impossible for the switch to
remain open or for the line to remain broken without warning the engineer or
other observer.
The accompanying Drawing represents the Invention embodied in one of the
various forms of which it is susceptible, the arrangement represented being the
most simple and most desirable known for practical purposes.

page_text: A represents the main track or railway; B, the side or switch track; and C, the
switch rails or switch proper, these rails being connected as usual by a rod a to an
upright rock-shaft C¹ provided with a hand lever, a half rotation by means of the
hand lever serving to open or close the switch; D, D, represent the main circuit
wires extending by the side of the railway track from the switch operating device
to a point at any desired distance therefrom and connected with the signaling
instrument F and the magneto-generator G, which will ordinarily be near each
other, but at a considerable distance from the switch; E represents a circuit closing
device consisting of two spring arms mounted in such position that they will be
acted upon and forced together to close the circuit by means of the crank-shaft C¹
which operates the switch, the arrangement being such that the circuit will be
closed and remain closed while the switch is closed, but be opened and permitted
to remain open whenever the switch is open.
The signaling instrument in the present instance consists of a vibrating arm
operated by means of an electro-magnet, and arranged to present different colored
glasses or shades in front of a lantern as it is moved to and fro.
b
Referring to the Drawings, 6 represents an upright post or support surmounted
by a lamp c; d represents an upright vibratory arm, the upper end of which is
provided with two different colored glasses e, one or the other of which will be
presented in front of the light according to the position in which the arm stands.
At its lower end the arm d is provided with an electro-magnet f mounted in the
main circuit D. This electro-magnet is arranged in front of and its core serves as
an armature to a permanent magnet g which will have its poles reversed in relation
to those of the electro-magnet. A spiral spring h connected with the lever d serves
to draw the electro-magnet away from the permanent magnet and to hold it in
that position during the time that there is no current flowing in the circuit.
During the time that the arm is in this position, which is its normal position,
the signal at its upper end is in position to indicate danger. Whenever a current
passes through the main circuit the electro-magnet f becomes incited and is
attracted towards the permanent magnet g, thereby moving the lever d and
causing the signal to change from the position indicating danger to that indicating
safety.
Passing next to the magneto-generator G, it will be seen to consist in the
present instance of a permanent magnet i and an electro-magnet or induction
coil, the latter mounted in the main circuit and arranged to vibrate or reciprocate
in relation to the permanent magnet. The electro-magnet ; is mounted upon a
horizontal swinging arm, and is actuated by means of an upright arm k on one end
of a horizontal rock-shaft H, the opposite end of which is provided with an arm or
treadle arranged by the side of the railway track in position to be depressed by
the wheels of the passing cars.
The operation of the apparatus is as follows:-
The switch being open, as represented in the Drawing, the circuit-breaking
devices E are released from the switch-operating crank, and the circuit remains
broken. If now a train approaches the switch it will act upon the lever l, and
cause the operation of the magneto-generator G, producing an electric current, but
as the circuit is broken this current will have no effect, and the signal will remain
in its normal position, indicating danger, thus warning the engineer that the switch
stands in an open position, or that the current has been otherwise broken, in either
of which cases will immediately arrest the motion of the train.
If however the switch be closed the switch-operating crank P bearing against
the circuit closing device e will maintain the continuity of the circuit. A train
approaching the track while the parts are in this condition will operate the
magneto-generator, and thereby transmit an electric current through the circuit to
the signaling instrument F. The effect of the current will be to excite the electro-
magnet f, which will immediately move the lever d, and thereby cause the signal
to indicate the condition of safety, from which the engineer will understand that
the switch is in a closed position and the signal is in an operative condition.

page_text: It will of course be understood that in order to have the signal remain in the
position indicating safety, the generator will be provided with an ordinary commu-
tator, whereby the current is caused to act continuously to hold the signal in the
position indicating safety. The apparatus may be operated without the commu-
tator, but as there would then be à repeated vibration of the arm or lever & the
use of the commutator is preferred. As soon as the train has passed the generator,
or shortly afterward, the electric current will terminate, and the signal will at once
fall back to the position indicating danger.
While the vibratory generator, as represented in the Drawing, answers a good
purpose, it is preferred to make use in ordinary cases of a rotary magneto-generator
constructed in any of the ordinary known forms, and provided preferably with a
commutator.
The rotary generator may receive motion through any suitable devices arranged
to be actuated by passing trains. Either of the forms of apparatus represented in
United States Letters Patent, No. 240,694, 240,695, 240,696, or that represented
in the application filed April 21, 1881, will answer a good purpose in this connection.
In place of the peculiar form of signal represented in the Drawing, any other
known or suitable form of electro-magnetic signal, either audible or visual, may be
used, provided the signal stands normally in the position indicating danger.
In place of the switch-operating crank and the fingers for effecting the
opening and closing of the circuit, any other suitable devices having a similar
mode of operation may be used, the only essential requirement in this regard
being that the opening and closing of the switch shall open and close the circuit.
Having thus described the Invention as communicated to me as the best mode
known of carrying it into effect, I wish it to be understood that what I desire to
protect under the hereinbefore in part recited Letters Patent is,―
1st. The combination with a railway of a magneto-generator, arranged to be
operated by passing trains, an electro-magnetic signal connected therewith, and a
circuit opening and closing device operated by the opening and closing of the
switch, substantially as described and shown.
2nd. In a magneto-electric switch signal for railways, the combination of a
magneto electric generator, an electro-magnetic signal in circuit therewith, said
signal standing normally in the position indicating danger, and a circuit closing
device arranged to be opened by the opening of the switch, and vice versa.
3rd. The combination of a magneto-electric generator adapted to be operated by
passing trains, an electro-magnetic signal in circuit therewith, and devices whereby
said circuit is broken whenever the switch is open.
4th. In combination with a magneto-generator C adapted to be operated by
passing trains a normally closed circuit D, an electro-magnetic signal F, and
circuit-closing device E, operating in connection with the switch-operating
crank C¹.
5th. In a magneto-electric railway signal, the combination of a magneto-
generator operated by passing trains, a signal and switch mechanism, arranged
substantially as described, to connect and disconnect the generator and signal.
6th. In a magneto-electric railway, the combination of an electro-magnetic signal
instrument, which stands normally in one position, a magneto-generator, an electric
connection between said instruments, which is normally closed, and means
substantially such as described for breaking the connection when the switch is
open.
7th. In a magneto-electric railway signal, a signaling instrument which stands
normally in a position indicating danger, in combination with automatic devices,
substantially such as described, whereby passing trains are caused to generate a
current, and thereby move the signal to safety when the line is unbroken, but at
no other time.
8th. The herein described method of indicating open switches on railroads, the
same consisting in adjusting a signal instrument to normally indicate danger,
connecting said signal in an electric conducting circuit opened and closed by

page_text: connections with the switch, and causing passing trains to transmit an electric
current through the circuit to move the signal from its normal condition when the
circuit is closed.
9th. In combination with a railway, a magneto-generator driven or caused to
operate by passing trains, a signal connected with and actuated by means of the
generator, and switch mechanism which controls the action of the electric currents
upon the signal.
10th. In combination with a railway switch, an electric signal to indicate the
position of the switch, and a magneto-generator operated or set for operation by
passing trains.
In witness whereof, I, the said William Phillips Thompson, have hereunto set
my hand and seal, this Fifteenth day of March, in the year of our Lord One
thousand eight hundred and eighty two.