Komatsu BR380JG-1E0, Shop Manual, Page: 378 / 841

30 Testing and adjusting SEN02305-01
BR380JG-1E0
37
Adjusting tension of crusher drive
V-belt
k
If the V belt tension is not normal, the V
belts will likely slip when the crusher starts
or stops, and shorten the service life of the
V belts drastically.
Open the V-belt inspection cover, then adjust the V-
belt tension as follows.
Tools to use
Handle: Accessory tool No. 14 or 15
Box wrench: Accessory tool No. 16
k
For details of the accessory tool, see
“Crusher accessory tool” in Mainte-
nance volume of the operation and
maintenance manual.
Guideline when checking V-belt tension
The deflection should be approx. 15 mm when 1 belt
is pressed with a finger force of approx. 6 – 7 kg.
If the V-belt makes a slipping sound when the
crusher is started or stopped, use the following pro-
cedure to adjust to the correct belt tension.
V belt tension adjusting method
The V belt tension may be changed by adjusting
the turnbuckle located behind the crusher motor.
After the adjustment, be sure to tighten the locknut.
1.
Open the V-belt inspection window.
2. Loosen locknuts (4) and (5) of crusher V-belt
adjustment turnbuckle (3).
(Locknut (5) turns in the opposite direction to
normal.)
Tools to use
Wrench: Accessory tool No. 1
Wrench: Accessory tool No. 11
k
For details of the accessory tool, see
“Crusher accessory tool” in Mainte-
nance volume of the operation and
maintenance manual.
3. Turn crusher V-belt adjustment turnbuckle (3)
to extend distance (L) between the yokes, then
adjust the turnbuckle so that tension load (F)
for 1 V-belt is 63.6 – 73.6 N {6.5 – 7.5 kg}.
(When this is done, deflection (a) is 15 mm.)
Tension load (F) is the average value of the
measured tension loads for 9 V-belts.
4. Start and stop the crusher 2 – 5 times.
5. Measure tension load (F) for 1 V-belt again and
check that the measured value is 58.7 – 68.7N
{6.0 – 7.0 kg). (When this is done, deflection
(a) is 15 mm.)
6. Tighten locknuts (4) and (5).
L/2
L
F
a
B A
B J Z 1 3 8 0 7