Brother RH-9820 Service Manual page 91

F
Belt tension adjustment for driving looper belt
<Standard installation when belt is tensioned>
<Belt tension adjustment>
1197B
0928B
0929B
Attach the timing belt (22) so that the distance
from reference line (A) (for installation: 65 °
position) on the looper base (b) to reference line
(B) on the bed is 5 mm or less when (d) of the
theta M pulley assembly (18) is touching against
the motor stopper (23), and then adjust tension
pulley (28) to the appropriate tension.
1) Place the timing belt (22) onto the looper base
2) Pull the tension pulley (28) in the direction of
Measurement
Measurement position
position
3) Check that the mechanism is at the <Standard
* Be sure to use a belt tension gauge to measure
* The belt tension gauge should be set to
NOTE:
RH-9820
(b), driving looper shaft assembly (9) and theta
M pulley assembly (18), and then provisionally
install the tension pulley (28) so that it is gently
pressing against the timing belt (22).
the arrow to adjust the belt tension so that
it is within the ranges given below.
・ When using a new belt: 80 - 90 N
・ When reusing an old belt: 60 - 70 N
installation when belt is tensioned> position
given above at this time. If the reference lines
are more than 5 mm apart, readjust the
mechanism.
the belt tension, and measure at the position
shown in the illustration.
measure a unit weight of 0.04 kg/m, a belt width
of 10 mm and a span length of 136 mm.
If you do not have a belt tension gauge, use a
push-pull gauge to push tension pulley (28) in
the direction of the arrow
N, and then tighten the two socket bolts with
washers (31).
6. ASSEMBLY
with a force of 65
82