Adjusting The Rear Needle Guard; Relation Between The Rocking Thread Take-Up Timing And The Needle Thread Loop - JUKI MF-7200D Instruction Manual

10. Adjusting the rear needle guard
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the fol-
lowing work after turning the power off and ascertaining that the motor is at rest.
1
A
B
2
2
11. Relation between the rocking thread take-up timing and the needle thread loop
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the fol-
lowing work after turning the power off and ascertaining that the motor is at rest.
In case sttch skppng or thread breakage occurs due to excessve large or small needle thread loop even when
performng threadng n case of usng stretchable threads or less stretchable threads descrbed n "Standard
threadng", change the needle thread drawng tmng of the rockng thread take-up and adjust the sze of needle
thread loop.
4
2
1. When screw 1 is loosened, the rocking thread take-up rotates due to the light weight. So, be careful. If
it rotates, refer to the item "Adjusting the rocking thread take-up".
2. Do not change the timing other than the aforementioned one since the sewing trouble will be caused.
3
4
3
4 mm
1
– 18 –
Adjust the lateral poston of rear needle guard 1 so
that t receves the needle wthn the range of B when
the needle s n ts lowest poston.
1) Adjust the heght wth setscrew 2 so that the ds-
tance from edge lne A of rear needle guard 1 to the
top end of rght-hand needle s 1.5 to 2 mm when
the top end 3 of the looper comes from the extreme
rght end to the center of rght-hand needle.
2) Make rear needle guard 1 slghtly come n contact
wth the rght-hand needle so that the clearance
between rght-hand needle and top end 3 of the
looper s 0 to 0.05 mm when top end 3 of the looper
comes from the extreme rght end to the center of
rght-hand needle.
In addton, make rear needle guard 1 slghtly come
n contact wth the medum needle so that the clear-
ance between the medum needle and top end 3 of
the looper keeps 0 to 0.05 mm when top end 3 of
the looper comes to the center of medum needle.
Perform the adjustment wth setscrews 2 and 4 .
1) Loosen screw 1 .
2) Move 2 forward or backward. The relaton between
the movng drecton and the sze of needle thread
loop s as shown n the table below.
3) After the adjustment, securely tghten screw 1 .
* Clearance between crank 2 and thrust collar 3 has
been factory-adjusted to 4 mm at the tme of delv-
ery. (Engraved marker lne on rockng thread take-
up shaft 4 algns wth the edge of crank 2 .
¡Sze of needle thread loop
Poston of crank 2 Move forward Move backward
In case of threadng Loop becomes
for standard seams
In case of thread- Loop becomes
ng for soft seams
Note : The adjustng drecton becomes reverse by way
of threadng. So, be careful.
Loop becomes
smaller. larger.
Loop becomes
larger. smaller.