IMPROVEMENTS IN RAILWAY SIGNALS, AND IN APPARATUS THEREFOR
Year: 1875

page_text: PROVISIONAL SPECIFICATION left by Thomas James Smith at the
Office of the Commissioners of Patents, with his Petition, on
the 23rd November 1875.-A communication from abroad by
Lieutenant-Colonel Victor Von Scheliha, temporarily residing in
St. Petersburg, Russia.
I, THOMAS JAMES SMITH, of the Firm of Robertson, Brooman, and
Company, of 166, Fleet Street, in the City of London, Patent Agents,
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN RAILWAY SIGNALS, AND IN APPARATUS THEREFOR," (communicated to me
from abroad by Lieutenant-Colonel Victor Von Scheliha, temporarily
residing in St. Petersburg, Russia,) to be as follows:
The object of this Invention is to lessen the dangers attendant upon
railroad traffic by means of a system consisting of simultaneously
given optic and acoustic signals.
Every two stations are connected by one wire. On each station there
are placed, besides a main and a relay battery, a station apparatus, a
station contact apparatus, and the necessary galvanoscope or relay
instrument. Between the stations at suitable points and proper distances

page_text: from each other are mounted the road signal posts, and the road contacts
pertaining thereto. The circuit is closed by hand at the stations and at
the signal posts in a thoroughly automatic way by the locomotive when
it passes under one of the contacts mounted along the road. Trains
moving in opposite directions are signallized by sets of optic and acoustic
signals, plainly to be distinguished from each other.
The mechanism by means of which these different signals are
produced differ only in so far as the magnets of the apparatus serving
to signalize a train going from, say, station A to, say, station B are
excited by the positive (+) current, whilst the negative (-) current
will affect the magnets which pertain to the apparatus that serve for
signalizing a train moving from station B to station A.
The station apparatus indicates to the station master the point reached
by a train that has left his station or is moving towards it.
Two electro-magnets the spirals of which are wound in opposite
directions, have their armatures swinging on the springs, small hammers
are attached to the armatures and to two bells of different tones; they
are made to ring by hammers so soon as one or other of the armatures
is attracted by its magnet it being excited by either the positive (+) or
respectively negative (-) current. Two pawls are attached to the a
armatures to make wheels turn the distance of one tooth; whenever a
magnet is made to attract its armature the wheels turn in opposite
directions. Catches prevent the wheels from at once turning more than
the distance of one tooth. A pointer hand is fastened on the axle of
one of the wheels, and another pointer hand on the other axle which
is hollow. One hand indicates the movement of a train going in
the direction from station A to station B whilst the other shows the
moving of a train going from station B to A. The number of
incisions or cogs of the wheel correspond to the number of bell strokes
which are given before and at the starting of a train, and to the number
of signal posts and contacts placed along the road between the two
stations.
"
On the dial there are marked two rows of numbers and letters, each
row containing as many numbers and letters as there are incisions or
cogs in wheels.

page_text: the two stations. On this diagram is marked the position of all signal
posts contacts with the same letters that are used on the dial.
The distances at which these signal posts and contacts are placed
from either station are also marked on the sketch. With the last bell
stroke produced by hand at the starting of a train from the station the
corresponding hand moves to the last number of its row or circle.
Hereafter the circuit is automatically closed every time the loco-
motive passes under one of the contacts placed along the road, when the
hand advance will one letter, until at last as a sign that the train has
safely reached the next station it again reaches another letter on the
dial. Should a hand stop at any one letter an indication is thereby
given that the train has also stopped at a point that by referring to the
diagram may easily be defined by the station master, and finally should
both hands move at once or at short intervals this is a sure sign that
two trains running in opposite directions on the same track are about to
collide. The signal "danger" is at once given, and both trains are
stopped in good time.
The station contact apparatus is made to operate by a relay battery,
and effects the closing of the circuit of the main battery by which the
magnets of the station apparatus and of the road signal posts are
affected. A small steel magnet has attached an electro-magnet with an
armature ending in a lever which turns on a pivot. If a current passes
through the spiral of the electro-magnet the lever is pressed down by the
spring and with it the bolt, which thus far has arrested the wheel that
is driven by a small weight. The wheel commences turning, but at
once siezes a lever which presses the armature back to the poles of the
magnet, whereby a bolt is brought back to its first position, and stops
the wheel after having made one revolution.
An excentric rod is lowered and raised during each revolution of the
wheel, and when having reached its lowest point it closes the contact
belonging to the main battery. Instead of the excentric rod the wheel
may be provided with a friction contact, or the whole apparatus may be
supplanted by a galvanoscope properly constructed. The road signal
post apparatus is mounted on guard houses or on a separate column.
The construction of this apparatus only differs as far as one bell is of
considerably higher tone than the other. This apparatus has a steel

page_text: magnet to which is attached an electro-magnet, which thus is rendered
a permanent magnet holding an armature. If a current be sent through
the spiral of the magnet the latter is magnetized in a sense opposite to
what it has been magnetized by the steel magnet, i.e., the poles of the
electro-magnet become changed from (+) into (-), and from (−) ·
into (+), whereby the strength of the steel magnet is as far neutralized
as to allow the spring to act upon the lever, and thus to jerk the
armature off the poles of the electro-magnet. If the armature is
jerked off the poles of magnet a bolt is withdrawn from the front of a
pin of a wheel, which driven by a weight is caused to revolve. Imme-
diately the lever which acts upon the armature is seized by a pin of the
wheel the armature is mechanically brought back to the poles of its
magnet, whereby the bolt returns to its first position and is made to catch
the next stopping pin of the wheel, thus stopping the wheel. As soon
as the wheel commences to revolve the lever is taken along by one of
the pins, and its movement is transplanted to the hammer that now
makes the bell ring.
The number of pins or incisions of the wheel that serve for acting
upon the levers is the same as the number of pins or incisions of the
wheels of the station apparatus; one of the wheels turns from right to
left, the other from left to right.
The electro-magnet of the bell work is affected by only the positive
(+) current, whilst the electro-magnet of the second bell work is
excited by only the negative (-) current. The axles of the wheels are
constructed similarly to the axles of the wheels of the stations apparatus, 1
i.e., one axle turns within the other one. On each axle there is fastened
a small paddle wheel turning within a closed casing, which is partially
filled with glycerine, an acid diluted with water, or any other fluid not
apt easily to freeze. This paddle regulates the movement of the wheel.
The weights by which the wheels are driven run in guides placed
within the hollow shaft of the column; the weights are wound up by
means of a crank; if the weight is entirely wound up or run down it
causes a bell to ring.
Two Optic Signals.-Around the axles of the wheels a cog wheel
turns loosely; catches are fastened on the wheel, one catch (by means;
of a pin) is thrown out of the cogs of the pinions as soon as the wheels
commence turning, and the weight is caused to sink. A chain is

page_text: provided with a support capable of raising a rod of the signal until the
catch which is attached to the signal rod has passed a snapper and is
resting on it. Each further partial revolution of one of the wheels
causes the weight to be again wound up. The signal remains up as long
as the train has not passed the signal post, but the train having passed
it disappears in consequence of the snapper by means of a lever being
withdrawn from under the catch. The dial is entirely covered by the
disc and a ring. The disc revolves on the axle of one of the wheels
from left to right, whilst the ring turns on the axle of the other wheel
from right to left. The number of letters marked on the dial corre-
sponds to those marked on the dial of the station apparatus; only one
of them in cach row is visible at one time through the excisions with
which the disc and the ring are provided.
In order to enable the engine driver readily to read a letter, and to
make him recognize from even a distance the point reached by his train
or by a train coming from an opposite direction, the disc and ring
are divided into quadrants differently coloured; at night. the dial is
illuminated.
An auxiliary signal arrangement consists of two contact keys placed
within the hollow shaft of the column; these keys are only accessible
after a door having been opened, to which the key is kept by the
conductor or by any other servant on the train. The closing of this
contact causes conventional signs to appear on the station apparatus,
and on the dials of all the signal posts placed between two stations;
thus a train that has stopped for any reason may place itself readily into
telegraphic communication with the two stations as well as with all the
Signal posts between them.
Road Contact Mechanism.-This contact is closed in an entirely
automatic way by the locomotive itself; it is not placed on the track
but above it, and is fastened to a signal post or to a separate pole. An
elastic arm is attached to a lever which turns, protrudes several inches
across the rail, and is seized by an arm attached to the locomotive; a
spiral spring regulates the return of the arm by a set screw, by it
the lever and the arm are kept in a perpendicular position to the track.
The contacts are perfectly isolated, but have ground connection. The
axle of the lever is connected with the air or line wire; the contact
springs are provided with a platinated copper plate, so on each side is

page_text: the lever. If the arm is seized and taken along by another arm the
lever according to the direction in which the train is running is thrown
against the positive (+) contact or against the negative (-) contact,
and the circuit is correspondingly closed. In the first case all apparatus
will work the magnets of which are affected by the positive (+) current,
whilst in the second case those apparatus are placed into function, the
magnets of which are affected by the negative (-) current. So soon
as the locomotive has passed the contact the spring will lead the lever
and its arm back into their normal positions.