AN APPARATUS FOR INDICATING THE SPEED OF RAILWAY TRAINS
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by Henri Adrien Bonneville at the Office
of the Commissioners of Patents on the 23rd May 1878. A communication
by Paul Emile Le Boulongé, of Liége, in the Kingdom of Belgium.
HENRI ADRIEN BONNEVILLE, of the British and Foreign Patent Offices, 18, Rue
de la Chaussée d'Antin, Paris, France, and 6, Piccadilly, in the County of Middlesex,
Patent Agent.
"AN APPARATUS FOR INDICATING THE SPEED OF RAILWAY
TRAINS." A communication from Paul Emile Le Boulongé, of Liége, in the King-
dom of Belgium.
The Invention relates to an apparatus for indicating the speed of railway trains,
which is set up along the side of the way opposite the points of danger, where the
engine drivers are enjoined by the regulations to slacken and not to exceed a fixed
speed. It marks the speed of the train by an indicating contrivance visible a long
way off when the said train arrives within about a hundred yards' distance of the
point of danger; the engine driver, seeing this indicator, has therefore time to
moderate his speed if it is too great.
The apparatus consists of a disc of blackened bronze of perfect equilibrium, sup-
ported by a standard, and moveable round a horizontal axis of cast steel. A weight
hanging from a silk string, which encircles a grooved pulley, solicits the disc to
turn, but the rotating motion is prevented by a stud abutting on the end of an
uncogging lever, the outside end of which is provided with a fork, between the prongs
of which passes a tapped vertical rod, on which are screwed an abutting nut and a
counter nut. On the upper end of the said tapped rod is secured the end of a small
chain passing over a check sheave, whilst to the other free end of the said chain is
hung a weight of about thirty pounds, and to the lower end of the tapped rod is
secured a small chain, which returns to a horizontal position in passing over a second
sheave, and is then prolonged by an iron wire along the side of the way, until
within about a hundred and fifty yards of the apparatus, where the wire is pro-
longed by a small chain which runs perpendicular to the way on a third sheave;
the small chain then passes on to the sheave of a click, to which it is secured by a
screw; and, lastly, on its free end is hung a counterweight of about ten pounds.
The said click is placed near the rail, outside the way; it is fitted on an iron rod

page_text: secured by screw bolts to two consecutive sleepers, and a lever, the tail of which
engages in a notch in the sheave, prevents the latter from revolving under tho
traction of the weight suspended to the end of the small chains above mentioned,
whilst the other end of the said lever is situated near the rail and at a level rather
higher than that of the said rail.
When the first wheel of the train reaches the click the wheel tyre presses down
the lever, and disengages it from the notch, the weight comes down, the abutting
nut raises the uncogging lever up against and inside the top of a mortise cut in the
frame, and the disengaged disc is set in notion.
The first wheel of the train, on arriving about fifty yards further on, encounters
a second click identically similar to the one that has just been described, and which
serves to raise a brake lever which carries a foot consisting of a flexible spring lined
with leather, which comes in contact with the circumference of the disc, and stops
its motion.
The sector traversed by the disc represents the average speed of the train, whilst
the axle-tree of the first carriage wheel is crossing the space of fifty yards between
the two clicks.
In order that the sleepers may not be displaced for obtaining, a distance of fifty
yards between the clicks, the latter may be adjusted at different points of the rod
that carries thein.
On a dial are painted in white the strokes and figures indicating the different
rates of speed; the centre of the said dial is cut away to the same diameter as the
disc, and this opening is closed by a glass showing a finger which stands out in
white from all the rest of the apparatus, which is black...
The indication of speed remains permanent as long as the guard does not put the
apparatus back into its first position for a following train. In order to effect this
operation the two weights are first successively raised; the counterweights then
causing their respective sheaves to revolve, the clicks are cocked automatically;
then a little door is opened, and by means of a handle the string of the driving
weight is wound up by causing the disc to revolve in the opposite direction until
the stop on the disc has passed the uncogging lever, against which it stops.