TM 55-203
position of the handwheel. For example, with a geared-
brake levers and rigging as the airbrake.
The
type, if the handwheel (fig 8-7) is horizontal, the
handbrake will always be Installed on the B-end of the
handbrake will be designated as a horizontal geared-
car; that is, the end toward which the brake piston
type handbrake; if the handwheel is vertical, as a
moves. Usually, the handbrake is connected to the
vertical gear-type Figure 8-8 illustrates a vertical lever-
cylinder lever, adjacent to the brake piston connection
type, geared handbrake. This type is designed for
or to some equivalent point. In general, handbrake
mounting on the ends of gondola freight cars. Figure 8-
equipment consists of a handwheel (or hand lever), a
6 illustrates a vertical, wheel-type, geared handbrake.
handbrake shaft, and handbrake connections which
With a horizontal-type brake, it is possible to transmit
include rods and chains connecting the handbrake shaft
the braking force directly from the hand-wheel to the
with the brake levers. In some cases, other parts, such
vertical shaft, as evidenced by the straight-shaft type of
as gears, pawls, and a bellcrank, are also used.
equipment. However, with a vertical-type, since the
braking force is applied initially in a horizontal direction,
c. Types.
Hand-operated brakes include the
some medium, such as gearing, is necessary to change
ordinary, straight-shaft handbrake equipped with a
the direction of the force from horizontal to vertical so as
handwheel at the top, which is turned to wind the brake
to transmit it to a point below the level of the
chain on or off the lower end of the shaft (fig 8-5); the
underframe.
ratchet type of brake, in which a lever and ratchet are
employed instead of the ordinary handwheel; the drum
e. Use. With a horizontal brake, as mentioned
or cone type, which employs a ratchet device; the
above, the braking force is initially in a vertical direction
geared brake, which has gears that assist in the
and can be transmitted to the bottom of the car by a
application of power (fig 86); and the screw type, in
vertical shaft. If a geared-type horizontal handbrake is
which the brake shaft is turned by means of a screw or
used, the braking force will still generally be transmitted
worm and a gear and the brake is applied by means of a
through a vertical shaft. However, with a vertical brake,
crank or toggle.
when the direction of the application of force changes
from horizontal to vertical, a length of chain connected
d. Classification. The types of handbrakes in use
to a vertical shaft normally is used to transmit
on cars can be further classified as either horizontal or
vertical The designation used will depend upon the
Figure 8-5. Straight shaft handbrake.
8-6
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