AN IMPROVED RAILWAY BREAK
Year: 1857

page_text: PROVISIONAL SPECIFICATION left by Eloi Jean Baptiste Ledure at
the Office of the Commissioners of Patents, with his Petition, on the
21st January 1857.
I, ELOI JEAN BAPTISTE LEDURE, of Paris, in the Empire of France, Civil
Engineer, do hereby declare the nature of the said Invention for "AN
IMPROVED RAILWAY BREAK," to be as follows:-
My improved railway break relates to the application of the rotating power
of each wheel of a railway carriage as its own break, by means of excentrics
fixed on the axle, the action being. so regulated that the pressure of the break
or rubbing surface may either be applied suddenly for immediate stoppage, or
progressively for ordinary stopping. For this purpose 1 fix two excentrics
near either end of the axle inside the frame, each being furnished with an
excentric rod extending horizontally in opposite directions. The excentrics
being fixed to the axle are always in motion during the rotation of the wheels.
Break surfaces are suitably supported from the carriage frame at opposite
diameters of the wheel, upon which the excentric rods are caused to act when
required. The excentric rods are held up at the free end by a link connected
with a bell-crank lever pivoted on the carriage frame, which is linked or
otherwise connected with a hand lever situate in any convenient part of the
carriage, which may be in connection with the whole of the excentric rods.

page_text: This lever is suitably held by a catch until released for the purpose of
throwing the breaks into action. To effect this, the motion of the hand lever
lowers the excentric rods, which, by a suitable catch or hook thereon, take
hold of the breaks & draw them at once forcibly against the tyre of the
wheel, that is, within less than one revolution of the wheel, which is thereby
stopped in its rotation. If the pressure is to be applied gradually & pro-
gressively, the motion of the hand lever causes the excentric rods to be thrown
into gear with a ratchet wheel whose axis is placed at the back of the break
surfaces.
On the axis of the ratchet wheel a camb or snail piece is placed, which
exerts a gradually increasing pressure on the back of the break as the ratchet
is caused to turn round, & thus to force the breaks against the periphery of
the wheel. Each revolution of the excentric causes the ratchet wheel to be
moved round one tooth. The wheel of the carriage may therefore perform
a considerable number of revolutions before the pressure is sufficient to
Stop it.
The two excentrics of each wheel are fixed on the axle in positions opposite
to each other, so that the pressure on opposite points of the wheel may be
simultaneously brought to bear. The hand levers are placed in connection
with rods sliding longitudinally in the carriage frame, which may be suitably
connected between the carriages, so as to unite the several rods in a train, by
which means the break action may be applied from any point, & simulta-
neously throughout the train. The links or connecting rods giving the motion
to the excentric rods, for the purpose of throwing them in or out of gear, are
connected with the longitudinal rod or rods, as before mentioned.