Sharp VC-MH80 Service Manual page 20

VC-MH80
CHECKING THE BRAKE TORQUE
Checking the brake torque at the supply side
l
Torque
Remove the cassette housing control assembly.
l
Make a short-circuit between TPSOOl and
l
turn on the power.
1.
Set a torque gauge to zero on the scale. Place it
on the supply reel disk.
2. Switch from the FF mode to the STOP mode.
AC power plug.
3. Disconnect the
Checking
l
1. Slowly rotate the torque gauge in the clockwise
rection of the supply brake so that the reel disk
and the indicator otthe torque gauge rotate at
an equal rate. Check that the values are within
t h e r a n g e o f C W d i r e c t i o n = 35+2OmN-m
(357 + 204gfcm), CCW direction = 10 + 4m N*m
(102 + 4lgfcm), and that the brake torque in the
CW direction is at least twice as high as that in
the CCW direction.
Supply reel
disk
Checking the brake torque at the take-up side
l
Remove the cassette housing control assembly.
l
Make a short-circuit between TP5001 and
l
TP5002, both located on the timer PWB. Now
turn on the power.
1. Set a torque gauge to zero on the scale. Place it
on the take-up reel disk.
2. Switch from the FF mode to the STOP mode.
AC power
3. Disconnect the
Checking
l
1. Slowly rotate the torque gauge in the clockwise
rection of the take-up brake SD that the reel disk
and the indicator of the torque gauge rotate at
an equal rate. Check that the values are within
the range of CCW direction = 35 + 2OmN:m
(357 + 204gfcm), CW direction = 10 + 4mN-m
(102 + 4lgfcm), and that the brake torque in the
CCVV direction is at
the CW direction.
Adjustment of the brake torque at the supply
l
side and the take-up side
1. If the supply or take-up brake torque is outside
the range, clean the supply or take-up reel disk
break lever pad, then recheck the torque.
2. If the supply or take-up brake torque is still out-
side the range, replace the main brake ass' y or
the main brake spring.
Note:
When the main brake is replaced, perform the
height checking and adjustment of reel disks (see
page 14), and the brake torque checking.
20
plug.
least
twice as high as that in