The morning call., 1890-07-07
TRAIN AIR-BRAKES.
Description of an Ingenious
Piece of Mechanism.
An Interesting Subject Upon the Details Of
Which Thousands Of Travellers Are
Little Informed

How many people who ride on railroad
TRANS have clear understanding of that
ingenious piece of mechanism known as
the ir-brake?"
This was the subject of a discussion
among party of gentlemen, the other
evening. at down town hotel. who had
commenced by relating personal expert
ences on the rail, and finally drifted to the
less exciting topic of air-brakes.
One Of the gentlemen present, who from
his occupation is obliged to travel many
thousands of miles on railroad trains in
the course of year, was asked to explain,
for the edifcation of the Others the manner
of working the continuance called an air
brake, and its application to modern rail-
reading.
The gentleman appealed to confessed
himself unable to furnish the desired in
formation, and expressed an opinion to the
effect that Of the people who ride on trains
equipped with air-brakes, not one in five
hundred had any definite knowledge con-
corning the utilization of air in controlling
a railroad train.
STRAIGHT AIR-BRAKE
The essential features OF the so-called
Straight AIT Train Brake" are:
First-A small vertical air-compressor is
placed upon the side of locomotive just
ahead of the engineers cab. This air-com-
pressor, actuated by steam from the loco
motive boiler, congresses air up to pres
sure Of from seventy to eighty pounds per
square inch.
Connected with this is an air-Storage res
ervoir, usually placed under the floor or
deck-plate of the cab A discharge pipe
leads upward from the reservoir to three
way cock attached to the boiler head direct
ly in front of the engineer. From this cuck
pipe extends backward under the locom0-
tive tender, and under the cars coupled be-
hind 1t, the connection with the air-pipe be-
tween cars and locomotive being made with
flexible piece of hose fastened together by
brass coupling with rubber gaskets or
joints, so designed that under air pressure
the rubber will slightly compress against
the sides OF the connection, forming an air
tight Joint.
THE ENGINEER's PART.
In operation the engineer by use of the
three-way cock connects the air-storage
reservoir as above described with the train
pipe, permitting the compressed air to flow
backward through the train, following
through branch pipes connecting with the
main train-pipe, entering the brake-cylin-
ders and forcing forward pistons fitted there
in, thus applying pressure along the piston
rods and through various forms of brake
rigging to force the brake-Shoes against the
wheels. This brake is released by another
turn OF the three-Way cock, closing con-
nection between train-pipe and storage
reservoir, and opening the traln-plpe to
the atmos here, permitting the air to
escape from the Undergraduates through
the traln-pipe, thus releasing the brakes.
An ingenious device is sometimes used in
connection with this form of straight air.
brake. to permit the release OF air directly
from the brake-cy climbers when the train
pipe is open to the atmosphere, but as this
does not affect the principle of the air
brake, detailed description Of this device
would be of little interest
BREAKING IN TWO.
II will be observed that in the case Of
train breaking in two at any point the de-
tached cars become entirely disconnected
from the air-brake power. From this cause,
between the years 1915 and 1880. and while
the straight air-brake which had taken the
| place Of the old Cramer device was in use,
accidents, especially to frelght-trains, were
OF frequent occurrence. 10 remedy this
defect MIR. Westinghouse perfected and in
troduced his automatic airbrake, which by
successive improvements has gradually
been brought to its present state of perfec-
zion. Like the straight-air, the automatic
brake requires the alr-compreSSer and air
storage reservoir attached to the engine,
and in addition to this an auxiliary reSer-
fUll 1bl tlS olOldHO VI All uuuGl CdSh anu
every car in a train. Unlike the straight
ar-brake, under the operation OF which the
brakes are released when the long train
pipe is empty, automatic brakes are held in
release only when this pipe is full OF air uu-
der pressure.
COUPLING THE PIPE.
The coupling of the train-pipe between
the cars is made, as in the straight-air,
with two pieces of flexible hose, the sec
lions being connected by clutch coupling
of ingenious pattern. perfectly tight when
in position, and readily separated without
breakage of attachments when cars are
pulled apart by accident or design, with
out first discOnnecting the air couplings.
When the automatic brake is in opera
ton compressed air from the pump passes
backward into the storage reservoir under
the locomotive, and into each storage or
auxiliary reservoir under the cars, and is
usually held up to the pressure of from
sixty to eighty pounds to the inch.
ENGINEER's BRAKE VALVE.
A so-caled engineers brake valve in this
form Of brake replaces the three-way cock
used in straight-air In applying the
brake the engineer, by simply turning the
handle of this valve, stops communication
between the air-pump, storage sreseryoirs
and train-pipe, allowing the air to escape
from this pipe. The air on its way from
the pipe just mentioned to the stor-
age cylinders repasses through what
Wuuiu appear DIV lHo uIab BIuuC6
to be a very complicated piece of mechan-
ism called triple valve, but which is
really very simple device. This valve is
so constructed that when air from the
train-pipe is reduced below the pressure in
the auxiliary reservoirs under the cars
communication is established directly be-
tween the auxiliary reservoirs and brake
cylinders, causing the brakes TO he applied
by advancing the brake-cylinder piston
and rod exactly as in the case of the straight
air-brake.
A SUDDEN STOP.
When a sudden stop is required to be
made, or should any OF the couplings be-
tween the cars become detached from any
cause, allowing air to quickly escape from
the train-pipe, communication between it
and the Drake-cylinder is automatically
made, permitting the instantaneous pas
sage of some portion of the air directly
from train-pipe to brake-cylinder and at
the same time opening communication be-
tween this cylinder and the auxiliary reser-
voir.
Thus under the operation of the auto
matte brake it will be seen that if this
coupling between any of the cars is acct
dentally severed the brakes are immedl-
ately and automatically applied.
On passenger trains each car is equipped
with conductors valve, which may be
used by the conductor TO control the brakes
from any car precisely in the same manner
as they are controlled under ordinary con-
ditions from the locomotive by the en-
gineer.
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TEMPERANCE IESSON