IMPROVE- MENTS IN RAILWAY SIGNALLING AND IN APPARATUS AND FITTINGS CONNECTED THEREWITH
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by William Lawson and Thomas
Forrest at the Office of the Commissioners of Patents on the 11th April
1883.
WILLIAM LAWSON, of the Town and County of Dumfries, Goods Station Master,
and THOMAS FORREST, of Glasgow, in the County of Lanark, Engineer, "IMPROVE-
MENTS IN RAILWAY SIGNALLING AND IN APPARATUS AND FITTINGS CONNECTED
THEREWITH,"
This said Invention has reference to special new or improved appliances and
fittings for giving more efficient Danger Signals to the Engine Drivers and Guards
of railway trains, and which will give increased safety against accidents, in all
weathers, or inattention on the part of these attendants.
And the nature and novelty of this Invention consist in connecting with the
rods or mechanism which work the semaphore or other signals of railways, and
automatic or simultaneous acting arrangement of mechanism which will oscillate or
slide an arm or plate with one, two, or more detonating signals secured on it (such
as those used at present for fog signals on railways) laterally over one or both rails,
and withdraw it (preferably placed some distance in advance of the signal post or
station) so that when the semaphore was at the danger position, the detonating
pellets would be exploded by the wheels of the engine or train, and give the
necessary loud noise or alarm to the engine-man and guard, to stop the train
before reaching the signal station, and remove the said plate and detonators off
the rails, when the semaphore is at " caution or "all right" signal, quite out
of the way of the wheels of the train, and prevent the detonators giving the alarm.
One arrangement of the mechanism and fittings for carrying and actuating the
said detonating alarm signals, consists of a carrying bracket preferably made of
cast steel in one or two parts, made with longitudinal flanges to grip the lower
head or flange and central web of the rail on both sides, and screwed tight by one
or more bolts and lock nuts, through the web and below the flange; and having a
strong snug arm projecting down at one end under the rail, with a hole up through
it to carry a strong vertical adjustable screw stem with nuts above and below, and
formed with a strong stud on its upper end parallel to and a little under the rail,
ΕΡ
"

page_text: so as to carry the oscillating two armed lever of the detonating plate. The upper
arm of this lever is curved out laterally from its oscillating centre or eye under the
rail up the out-side of the rail, and by a flange on top carries the thin plate or plates
resting on the top of the rail with the detonating pellets properly secured on their
upper sides.
The lower arm of this lever would project down and work in a recess below the
rail, and be directly jointed to one end of a horizontal reciprocating rod (or one of
a set of preferably solid rods or tubes, to give positive action in both directions in
pushing and pulling without weighted levers) the other end of the rod being
connected by a bell-crank lever, or two levers, to a vertical reciprocating rod
connected to the lever arrangement which actuates the semaphore signal arm or its
lever, the rods and levers being all adjusted and set as before stated, so that when
the semaphore is raised to the horizontal danger signal, the new lever arrangement
would simultaneously oscillate the thin plates with the detonating danger signal
in over the rail, so that if the locomotive or train passes this part of the railway,
from any cause, the wheels would then explode the detonators and alarm the Driver
and Guard of the train. And when the semaphore lever was lowered either to the
half way down, or lowest positions, being "caution," and "All Right." Signals
respectively, then the upper arm of the lever carrying the detonators would be
oscillated outwards away from the rail, and it might be into a covered-in box in
the ground outside the rail, so as to protect the detonators from the weather,
accidents, or being tampered with.
When these detonating signals are to be used on both rails of the line, then the
said new bracket and detonating plate and lever fittings, would be mounted as
described on the other line of rails, and the lower arms of both levers connected
by two rods to the reverse arms of an oscillating vertical lever mounted on a
bracket, all between the rails and sleepers, so that the detonating levers would
act simultaneously in opposite directions outwards from their respective rails.
When the detonating signals are desired to be given some distance along the rails
from the signalling post station, then the said detonating lever mechanisin would
require to be fixed to the rails at that point, and its transverse rods would require
to be actuated by intermediate long rods or tubes along the side of the railway (in
the manner that points are worked at some distance from the signal station)
connecting these with the actuating lever mechanism of the semaphore or other
signals, or the rods working these. And although the detonators and thin plates
carrying these have been described as oscillated over the rail, it will be evident
that these might be reciprocated in guides level with the top of the rail, actuated
by reciprocating rods direct or through levers arranged horizontally in the manner
that the shifting or deflecting points are worked.
It is to be understood that for the perfect working, or positive action in pushing
and drawing of these detonating signals on to or off the rails, or vice versu, the
rods to which they are connected between the signal cabin and signal post, should
be constructed of tubes or solid rods, instead of wires and chains, as is the case in
some instances.