IMPROVEMENTS IN CON- TINUOUS AUTOMATIC RAILWAY BRAKES
Year: 1877

page_text: PROVISIONAL SPECIFICATION left by George Frederick Redfern at the
Office of the Commissioners of Patents on the 1st May 1877. A communication
from abroad by August Kraemer, of Augsburg, in the Kingdom of Bavaria,
and Sigmund Stern, of Warsaw, in the Empire of Russia.
GEORGE FREDERICK REDFERN, of the General Patent Office, 4, South Street,
Finsbury, in the County of Middlesex, Patent Agent. "IMPROVEMENTS IN CON-
TINUOUS AUTOMATIC RAILWAY BRAKES." A communication from abroad by August
Kraemer, of Augsburg, in the Kingdom of Bavaria, and Sigmund Stern, of Warsaw,
in the Empire of Russia.
The Invention communicated to me consists in improvements in continuous
automatic railway brakes, whereby the heaviest railway train can be brought to a
standstill with great security and promptitude, whatever may be the speed of motion
of the train; and the improvements consist, mainly, in the employment of a series of
discs fixed on the axles of the carriages in combination with other discs having a
sliding motion on the axle, whereby large frictional surfaces are obtained, such
sliding discs being pressed against the fixed discs by the action of steam or com-
pressed air (or otherwise), by the arrangements herein-after described.
To carry out the Invention communicated to me, one or more strong flat dises is
or are firmly fixed on to the axle of a railway carriage so as to rotate with it. On
each side of the said disc or discs is placed another disc which can slide on the axles,
a space being left between the fixed and moveable discs. The whole of the discs
are enclosed by a cylinder fixed to the carriage, and in which the axle turns steam-
tight. It should also be understood that the sliding discs fit steam-tight between
the axle and the interior of the cylinder, while the circumference of the discs fixed
to the axle is somewhat less than the interior circumference of the cylinder, so that
they may turn freely within it. The cylinder is so suspended from the carrriage
by suitable straps, and a vertical bolt, as to allow the cylinder to follow the move-
ment of the axle. The sliding discs may be brought against the discs fixed to the
axle either by means of steam from the boiler of the locomotive, conducted by
means of tubes into the cylinder, or by means of compressed air, produced by a
suitable air-compressing pump on the tender, or from a reservoir of compressed air
at about six atmospheres, and upwards, placed either in the tender or in the guard's
A main pipe jointed to allow of the motion of the carriages conveys steam
van.

page_text: from the locomotive, or compressed air from the reservoir or air pump, as the case
may be, to other pipes or tubes branching off near the axles of the carriages, and
parallel with the disc cylinders, such branch tubes having smaller branches opening
into the disc cylinder so as to convey the steam or compressed air into the spaces
between the sliding dises, such admission of the steam or compressed air being
effected when the brake is to be put in action by the opening of a valve in the main
pipe. The escape of the steam or compressed air when the brake pressure is to be
stopped takes place through a valve in a suitably placed branch pipe.
To prevent the rotation of the sliding discs when pressed against the rotating
discs cach sliding disc is provided with two horizontal slotted rods, through the
slots of which pass vertical rods, fixed to the disc cylinder, and provided with
strong spiral springs for carrying back the sliding discs from contact with the
rotary discs when pressure is removed, and also to keep the discs asunder during
the ordinary motion of the train.
The disc cylinder is provided with small holes for the escape of any air which
may accumulate between the sliding and rotary discs.
The pressure of the steam or compressed air may also be exerted on the inner
sides of the carriage wheels if flat wheels are employed; or if spoked wheels are
employed against discs fixed thereto by employing a disc placed outside each end
of the disc cylinder, and connected by means of rods passing through the ends of
the cylinder with the end sliding discs within the cylinder.
I would here observe that for the purpose of economizing steam, or otherwise,
when compressed air (compressed by a pump) is used for working the brake the
motion of the locomotive or tender may be employed after shutting off the steam
for working the compressing pump.
This mode of using the automatic brake pressure is particularly applicable for
stopping trains at the ordinary stations, as it is easy to determine the moment at
which the brake should be applied, in order to bring the train to a standstill at the
desired place.
Instead of fixing the discs and cylinder on the axle, as herein-before described,
the whole arrangement may be adapted to a cylinder, which may be fitted on and
fixed to the axle.
It will be easy to understand that these improvements may be carried into effect
without the axle being in contact with the disc cylinder, the sliding discs in this
case being connected with the moveable discs outside the cylinder, so as to produce
pressure on the rotary discs without loss of power, and so as to avoid any contact
with the axle; or the same effect may be produced by the employment of cylinders
separated from but parallel with the axle.
The size and strength of the various parts of the improved brake will naturally
vary with the amount of brake power required, and on this will also depend the
number of brake apparatuses required for each train, as also whether or not the
pipes or tubes conveying the steam or compressed air to the cylinders should be
applied on one or both sides of the carriage.