IMPROVEMENTS IN AND APPER- TAINING TO SIGNALLING APPARATUS FOR AUTOMATICALLY SIGNALLING THE APPROACH OF TRAINS ON RAILWAYS
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by William Phillips Thompson at the
A
Office of the Commissioners of Patents on the 25th January 1882.
communication from abroad by Wesley Ward Gary of Boston in the County
of Suffolk in the State of Masachusetts United States of America.
WILLIAM PHILLIPS THOMPSON of the Agency for Foreign Patent Solicitors
6 Lord Street Liverpool in the County of Lancaster and of 323 High Holborn in
the County of Middlesex Civil Engineer. "IMPROVEMENTS IN AND APPER-
TAINING TO SIGNALLING APPARATUS FOR AUTOMATICALLY SIGNALLING THE
APPROACH OF TRAINS ON RAILWAYS." 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 following is the description of the Invention as communicated to me.
The object of this Invention is to provide a simple reliable and inexpensive
signal mechanism for use at crossings curves stations and all other places at which
audible or audible and visual warning is to be given when trains are approaching.
It is the particular aim of this system to produce long continuing signals
electrically without the aid of batteries to render the system entirely automatic
and to actuate or propel a signalling device in a continuing manner by appliances
acted upon by passing trains.
The Invention embraces the combination with a magneto-generator or dynamo-
machine of any approved style of appliances whereby the generator is driven from
passing trains in a continuing manner or with a long continuing action so as to
develop a prolonged electric current or succession of currents.
It also embraces means whereby the generator may be continued in action after
the passage of the actuating train and until the train has reached the distant
crossing or other signal station.
It embraces also for the purposes above named means whereby the generator
may be driven with a positive action from passing trains and give sufficient
momentum to continue in action a considerable length of time: and also with the
same end in view. equivalent means which are set for action by the passing trains
and which impart to the generator automatically after the passage of the train a
continuing action.

page_text: The Invention further embraces the combination with a generator actuated with
a continuing action from passing trains as above described of a signal bell or
equivalent audible or audible and visual signal mechanism propelled or driven by an
electro-magnet in circuit with the generator.
It embraces also numerous details and modifications hereinafter explained.
Delicate galvanometer needles have been moved momentarily and visual devices
released by means of a magneto-generator actuated momentarily by passing trains
the generator embracing a vibratory member which received a single movement
from a passing car wheel-In practice the said devices proved worthless and were
consequently abandoned-The system differs from all others preceding it in that
the generator receives a long continuing motion in that it continues in motion after
the operating train has passed; and in that the currents produced as described are
applied to propel or. actuate the signal instead of merely releasing the same-Under
this system the generator may be placed a long distance in advance of the crossing
or station and the alanın continued from the time the train reaches the generator
until it reaches the signal station.
The following are the principal parts of an automatic bell alarm signal.
1st. The ordinary railway track or rail-2nd the signal instrument located at
the crossing or other point to be guarded-3rd the magneto-generator located by
the side of the track at any suitable distance from the signal, the distance varying
from a hundred yards to half a mile or more according to circumstances. The
electric currents generated in the inagneto generator are transmitted as hereinafter
explained to the signal through conductors or circuit wires. The conductors may
be laid in or upon the ground or mounted upon poles or one or both the rails
properly insulated may be employed as a conductor.
One form of generator consists of an armature provided with coils or spools of
insulated wire and arranged to revolve near the poles of a permanent magnet in
any-ordinary manner, -the-device-being a common form of magneto electric_
generator well known to those skilled in the art. The shaft on which the
armature is mounted is provided with a heavy fly-wheel and also with a pinion,
the latter driven by a gear wheel which is in turn mounted upon the same shaft
with and driven by a pinion-This 2nd pinion has secured to its side a ratchet
wheel which receives notion from a pawl pivoted to a weighted lever which
Jatter is mounted loosely on the shaft of the ratchet wheel-Immediately below
the weighted lever there is a vertically swinging arın secured to one end of a
horizontal rock-shaft which has its opposite end provided with an arm or treadle
arranged in position to be depressed by the passing car wheels-Each wheel in
passing depresses the arm or treadle aforesaid and thereby elevates the swinging
arm which in turn raises the weighted pawl-carrying arm-As soon as the car
wheel leaves the treadle and releases the parts, the weighted arm commences to
descend and through the intermediate gearing imparts a rapid motion to the rotary
armature thereby developing in accordance with the well understood principles a
strong electric current or succession of currents-The weight of the balance or
fly-wheel gives great momentum and causes the generator to continue in action a
considerable length of time after the train has passed and after the weighted arm
has completed its descent which requires considerable time-As the weighted arm
will fall a short distance after the passage of each car wheel or truck and before the
action of the next one the generator receives from each train a series of impulses
whereby its motion is greatly accelerated-A spring may be used in place of the
weight to depress the pawl-carrying arm or the two may be combined-In place
of the pawl and ratchet a friction clutch of ordinary construction may be employed
-The essential feature of the generating apparatus consists in the employment of
devices moved by passing trains to operate the generator in a continuing manner
after the action of the train has ceased, and it is manifest to the skilled mechanic
that the details may be modified to any extent desired-The generator above
described developes and transmits currents of alternating polarity for the reason
that the bell signal is made without a circuit breaker-When used with a bell

page_text: having a circuit breaking or reversing device the generator will be provided with
an ordinary commutator so as to transmit a constant current of one polarity.
The signal instrument has two bells and an intermediate vibratory striker.―The
striker is pivoted above its lower end, and provided on the lower end with a coiled
armature or electro-magnet which vibrates between the poles of two stationary
permanent magnets which are arranged with their opposite or unliko poles facing
each other. Two adjustable tension springs attached to opposite sides of the
striker hold the striker and armature normally in the intermediate position. The
circuit wires or conductors are connected with tho coil of the armaturo or electro
magnet in such manner that the currents of alternating polarity induced by the.
generator are transmitted to and passed through said coil.-The consequence is
that the armature is given an alternating polarity and caused to vibrate between
the permanent magnets and actuate the striker as long as the generator remains in
action.
A more simple generating mechanism which is driven directly or positively by
the train and caused to remain in action thereafter may be described as follows.
The vertical shaft mounted in fixed bearings at the side of the track carries a
fly-wheel coiled armature or induction coils and a cross bar the latter having its
ends provided with pivoted dogs which yield in one direction only.
A horizontal rock shaft is provided at one end with an arm in position to be
depressed by passing trains and at the opposite end with a swinging counter
weighted other arm which acts against the end of a bar in the vertical shaft and
thereby imparts a rapid rotation to the said vertical shaft and its attachments.
This swinging arm is provided with a weighted extension on one side in order to
return the arm and treadle to their normal positions.-The ends of the cross bar
are connected thereto by knuckle joints and held normally in position by springs.-
They yield in a backward direction only, so as to pass the arm without being
stopped thereby.-Instead of jointing the ends of the bar on the vertical shaft the
end of the swinging arm may be jointed in the same manner to swing forward and
permit the ends of the bar to pass over it.-In order to bring the ends of the bar
on the vertical shaft when at rost in position to be acted upon by the swinging
arm the lower end of the vertical shaft may be flattened and a spring arranged to
bear thereon. The same end may be secured by providing the vertical shaft with
three radial arms or more; as one or another will then be in position at all times to
receive motion from the vertical arın.-Or, in place of the cross bar a ratchet wheel
may be used upon the vertical shaft in which case a swinging counter weighted
arm acting thereon must yield laterally to allow the wheel to continue its forward
motion.
The generator described above is actuated positively during instead of after the
passage of the train; but like the first described machine it remains in action for a
long period of time.-It may be connected with an ordinary magneto-electric
signal bell or used with a signal of any suitable pattern and with or without a
commutator.
Another variety of generator may be described as follows. A vertical shaft
mounted by the side of the track carries the fiy wheel, a wound armature or
induction coil and three radial arms the latter arranged in such position that
each train in passing will act upon one of the arins and thereby impart a direct
and positive motion to the shaft its armature and fly wheel.-The fly wheel will
cause the the parts to remain in motion quite as long as it will be required to
operate the signal.-The armature used in this generator consists as shewn of a
Bat ended soft iron bar having the coil or spool of insulated wire at the middle
and having its ends arranged to revolve between the poles of parallel V shaped
permanent magnets.
The arms should be made to yield in a backward direction so that they may not
be stopped by striking the train after being set in motion; but if the train is
provided with a single projecting device to strike the arms the yielding action will
not be required, the arrangements of the yielding arms can be varied so as to yield

page_text: to a limited extent in a forward direction with a spring action.-This relieves the
shock and strain when the train encounters the generator and is an important
feature. A spring or cushion may be applied in any suitable manner either to the
generator or to the train for the purpose named.
In another modification a generator is provided with an armature or induction
coil which has a vibratory instead of a rotary motion between the permanent
magnets. The armature is mounted on one end of a centrally pivoted lever which
has its opposite end slotted and vibrated by a crank.-The crank shaft is driven
through its pinion from a gear wheel which latter has a vertically moving arm
mounted upon its shaft and connected thereto by a friction clutch which permits
the arm to rise independently.-A spring serves to draw the arm downwards and
set the mechanisin in motion. The elevation of the arm is effected by one arm of
a rack-shaft having a second arm or treadle arranged for depression by the car
wheels or other parts of the trains.
Instead of the above a rock-shaft similar to those mentioned above sets in
motion a pendulous arinature which swings to and fro repeatedly and for a con-
siderable period of time past the poles of the permanent magnets the poles of which
alternate as indicated.-If desired a fly wheel may be applied as in the preceding
machine to prolong the vibratory motion.
It is to be understood that in some instances the rock-shaft may be replaced by
a lever pivoted in the middle with one end in position to be depressed by the train
and the other end in position to elevate the actuating arm of the generator and
also that in place of the falling arms to move the generator racks and pinions
pulleys and straps or equivalent means for converting a vibratory into a rotary
inotion may be employed.
A visual signal or target may be secured to the striker arm or omitted or
modified as preferred.