NEW OR IMPROVED MODES AND MEANS OR APPARATUS FOR SIGNALLING OR COMMUNICATING BETWEEN PASSENGERS AND SERVANTS IN RAILWAY TRAINS
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by Edward Gilbert and Arthur Edward
Gilbert at the Office of the Commissioners of Patents on the 1st June 1880.
EDWARD GILBERT, of Dundee, in the County of Forfar, and ARTHUR EDWARD
GILBERT, of the City and County of Edinburgh, North Britain.
"NEW OR
IMPROVED MODES AND MEANS OR APPARATUS FOR SIGNALLING OR COMMUNICATING
BETWEEN PASSENGERS AND SERVANTS IN RAILWAY TRAINS."
This Invention relates to new or improved modes and means or apparatus for
communicating by signals between the passengers in the carriages and the guard
or other servants in railway trains, which apparatus is specially designed to be
applied in combination with continuous pneumatic or vacuum brakes to allow
passengers to apply these brakes and stop the motion of the train on the occurrence
of danger or serious alarm; and the object of which is to render such signalling
apparatus certain and efficient in its action, and most easily operated by any railway
passenger.
The Invention consists essentially in using the power of the pueumatic pressure
or vacuum which actuates the continuous brakes of a railway train to apply these
brakes, and simultaneously cause the display of a semaphore or other visible signal
to the guard or driver, by the simple action of any passenger pulling a cord, or
pushing or pulling a handle, or lever, in the carriage or compartment, to admit the
air to or allow it to escape from the pneumatic tubes of the brake.
Under one modification of the improved apparatus as applied in combination
with continuous brakes operated by pneumatic pressure, a close cast iron or other
metal box or casing is bolted or otherwise fitted to the ends of each carriage of the
train, preferably at or near the top, and an iron branch pipe or flexible tube coupled
to and leading from the continuous main pneumatic tube of the brake actuating
mechanism is screwed or otherwise connected to this box or casing, and communicates
with its interior by a small port or opening formed with a seat inside for a conical
or other valve, through which the air of the pneumatic brake tube is admitted
to the interior chamber of the box or casing only when this valve is open.
This conical valve is formed on the close end of a metal tube, fitted to slide air-
tight in a flanged bush passing through the end board of the carriage, the outside
Hange of which bush forms the back of the valve casing or box, and the valve is

page_text: kept closed on its seat by the power of a spiral spring fitted round the valve tube,
or by weights or other equivalent when vertical. A long bolt or rod is fitted into
the tube of the conical valve, and also presses on and tends to keep the valve
closed by means of a supplementary spiral or other spring fitted round its other end,
which passes through a box or casing fitted inside the carriage opposite the outer
or valve casing. The valve tube has a slot or slots cut in it, in which a pin on that
end of the bolt or rod is free to move when the bolt is partially withdrawn against
the action of its spring by any passenger pulling a cord attached to its inner end;
but when this pin on the bolt has traversed the length of the slot, the continued
pull on the cord also lifts or opens the conical valve against the power of its spring
or weight, and freely admits the air by the branch pipe from the pneumatic main
brake tube beneath the carriage. When the bolt is fully withdrawn to open the
valve, it is retained in that position, by means of a flange formed on it, against
which the spring also bears, and which flange is engaged by a spring catch. The
air under pressure entering through the valve to the casing thence passes into a
horizontal tube which is open to the casing, into which it is screwed, and in this
tube, which extends out to the side of the carriage, a long piston is fitted having a
semaphore or other signal attached to it, which, when the pressure of the air forces
out the piston, is displayed to the guard or driver of the train. This piston is forced
outwards in its horizontal tube, until it passes a small air hole or opening through
which the air now escapes, and the pressure in the pneumatic brake tube being at
once relieved, the brakes are applied automatically to arrest the motion of the train,
and thus also attract the attention of the guard; the escaping air being also, if
desired, made to blow an alarm whistle. The guard or other railway servant in
answering the passenger's summons, releases the spring catch to free the bolt and
close the air valve, and at the same time replaces the semaphore in its original
screened position at the end of the carriage, where it is fitted in a metal box for
protection, and kept from slipping out by the shaking motion of the train, by
means of the friction of a spring blade or other equivalent, or by its own weight
if the piston and tube are inclined or vertical. The air valve in the casing at the
end, or at both ends of each carriage, is preferably opened by a cord extending from
end to end of each carriage through each compartment (or it may be outside if
desired), and when the cord is pulled to open the air valve in any carriage, and
apply the brakes, the semaphore or signal for that carriage, or its particular end,
is displayed, and shows the guard where to proceed; the compartment whence the
signal originated being ascertained by the rope being slack in that compartment,
and the object of the pin and slot in the valve tube being to leave the cord slack
when acted on for this purpose. To prevent tampering with the rope when slack,
it may be held by passing over a roller at an angle, or by other frictional means.
Instead of employing a cord for actuating the air valve and signalling apparatus,
the withdrawal of the spring bolt and opening of the valve may be effected by a
bell crank and handle, with an ordinary bell wire, or the valve may be reversed and
opened against the pressure of the air by pressing a knob or lever to admit the air
to the valve casing, and to act on the semaphore piston. The semaphore also need
not be directly attached to the acting piston in the horizontal tube, but may be
hinged or jointed, and screened by being held in a vertical position at the end of
the carriage by a spring catch, which would be released to allow the semaphore to
fall out at an angle, or horizontally, by the action of the piston, when it is forced
out. For use at night the semaphore or signal may also be fitted to display a
coloured light or lamp, or to explode a fog signal.
In applying the improved signalling apparatus in connection with continuous
vacuum brakes, the arrangement and construction of the apparatus need not be
very different from that described as used in combination with brakes worked by
pneumatic pressure; but the air being now admitted in the reverse course, through
the valve casing to the vacuum brake tube beneath the carriage, to apply the
brakes the semaphore piston would be acted on by suction on the opening of the
conical valve, and would be made to open a supplementary or air admission valve,

page_text: during or at the end of its traverse, for the purpose of destroying the vacuum in
the brake tube; and the semaphore would either be displayed on the opposite side
of the carriage, or acted on by levers to display it at the same side.
The improved signalling apparatus is obviously susceptible of modification in its
details, as for example, in the means employed for opening and closing the air valve,
as by rubber or other springs or weights, instead of the spiral springs described as
being used, and in the kind of signals and mode of displaying these, without
departing from the essential features of the Invention, by which a signal is
displayed and the brakes applied simultaneously, by admitting and directing the
air of the pneumatic brake tube to operate this signal and the brakes when any
passenger pulls a cord or moves a handle or lever connected to an air admission
valve; or, in the case when vacuum brakes are used, by destroying the vacuum
in the main brake tube in the same manner.