TCM FB-8 Series, Руководство по обслуживанию, Страница: 69 / 259

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(3) Automatic clearance adjuster
T h e a u t o m a t i c c l e a r a n c e a d j u s t e r
a u t o m a t i c a l l y k e e p s t h e l i n i n g - t o - d r u m
clearance properly. The components are as
shown in Figure 5.7. It is put in action when the
brakes are applied while traveling backward.
■
Operation of the automatic clearance
adjuster
When the brake pedal is pressed down in
reverse travel, the secondary shoe is slightly
turned together with the brake drum, and the
lever is turned clockwise around the section
A
shown in Figure 5.7.
At this step, the section
B
of the lever turns
the adjuster. As the braking force becomes
stronger, the more force is applied to the
threaded area of the adjuster, and the force of
the lever cannot turn the adjuster.
When the brake pedal is released, the brake
shoe returns to the initial position, the lever
turns counterclockwise around the section
A
,
and the section
B
moves downward.
If a tooth of the adjuster is aligned with the
section
B
of the lever, the
B
is in mesh with
the next tooth and the clearance is adjusted
within the range from 0.25 to 0.4 mm [0.0098 to
0.0157 in.].
Fig. 5.7
CABLE
GUIDE
LEVER
SPRING
ADJUSTER
Fig. 5.8 Automatic Clearance Adjuster
Expanding direction
5. BRAKE SYSTEM