JUKI MF-7900-E22 User manual

MF-7900-E22,23
INSTRUCTION MANUAL

i
CONTENTS
I. SPECIFICATIONS.............................................................................................................1
II. IN CASE OF USING E22 .................................................................................................1
1.Installing procedure ..................................................................................................................... 1
2.Adjustment procedure ................................................................................................................. 5
III. IN CASE OF USING E23 ................................................................................................6
1.Installing procedure ..................................................................................................................... 6
2.Adjustment procedure ................................................................................................................. 8
IV. WITH REGARD TO THE ACCESSORIES (TENSION ROLLER) ..................................9
1.Installing procedure ..................................................................................................................... 9
2.Adjustment procedure ............................................................................................................... 10
V. DRAWING OF THE TABLE ...........................................................................................12

– 1 –
II. IN CASE OF USING E22
1. Installing procedure
1) Installing the binder close/open knee switch
Install the binder close/open knee switch under the
machine table with wood screws 󰿿.
󰿿
I. SPECIFICATIONS
Model MF-7900-E22, MF-7900-E23
Model name E22 : Machine for attaching endless spandex elastic tape
(With manual open/close type binder)
E23 : Machine for attaching endless spandex elastic tape
(With pneumatic open/close type binder)
Sewing speed Max. 5,000 sti/min (at the time of intermittent operation) (provided with PL12 or 13)
Speed of stitch at the delivery. 4,000 sti/min (at the time of intermittent operation)
(provided with PL12 or 13)
Needle gauge 3-needle 5.6mm, 6.4mm
Differential feed ratio 1 : 0.6 to 1 : 1.8 (Stitch length less than 2.5 mm)
Provided with micro differential feed adjustment mechanism (Micro-adjust)
Stitch length 0.9 to 3.6 mm (Adjustable up to 4.5 mm)
Binder open/close amount 40mm
Needle bar stroke 33mm (35 mm in the case the eccentric pin is changed over)
Noise -
Equivalent continuous emission sound pressure level (LpA) at the workstation :
A-weighted value of 79.5 dB; (Includes KpA = 2.5 dB); according to ISO 10821-
C.6.2 -ISO 11204 GR2 at 4,500 sti/min.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the follow-
ing work after turning the power off and ascertaining that the motor is at rest.

– 2 –
2) Installing the binder open/close device
Fit spacer 󱀀and install binder open/close device 󱀁
with screws (plus-minus screw, black, screw shank
length 8 mm) 󱀃.
Readjust screws 󱀃when the device does
not return smoothly.
Loosen the screw 󱢻in collar 󱀂. Adjust the spring
pressure of the binder open/close device. After the
installation of the open/close device, apply grease
(exclusive grease; JUKI part number: 13525506)
supplied with the device to B section.
3) Installing the lever
Install lever asm. 󱀄with screws (Slotted screw,
black, screw shank length 14 mm) 󱣂.
Apply the grease supplied with the machine to the
contact section A of lever asm. 󱀄.
Conrm that there is a clearance at section
A after installing the lever asm.
4) Installing the binder and the elastic guide
Install binder 󱀅and elastic guide 󱀆.
󱀆
󱀅
󱀁
󱀀
󱀂
B
󱀃
󱢻
󱀄

󱣂

– 3 –
5) Installing the chain and pulley
Install chain for binder open/close 󱀇to lever asm. 󱀄
with S-hook 󱢳. Suspend the chain through hole 󱢴
in the table. Adjust the longitudinal position of roller
asm. 󱢶 so that the chain ts in the roller groove. Fix
the roller asm. with wood screw 󱢵.
When the chain is installed in the state that the
position of the groove of the roller and the chain
is not proper, abnormal friction of the chain
occurs. So, install the chain with care.
6) Connecting the chain
After installing roller asm. 󱢶, t the chain to the groove
of the roller, put S-hook 󱢳in the top-end hole of open/
close lever 󱢷, and connect the chain.
Adjust the longitudinal position of lever block 󱢸
so that the chain smoothly ows in the groove of
the roller when open/close lever 󱢷works.
󱢶
󱢵
󱢳
󱢷
󱢶
󱢸
󱀄
󱢳
󱀇
󱢴

– 4 –
󱢹
󱢺
󱢽
󱢾
󱢼
󱢻
7) Installing the AK solenoid cord
Install AK solenoid cord 󱢹 as illustrated in the gure.
Route the cord behind presser bar lifting lever 󱢺.
If the cord is routed in front of the lever, the
cord can be caught under lever 󱢺, resulting
in a breakage of the cord.
Fix the cord with cord band 󱢻. Pass the cord between
thread trimming sensor 󱢼and the frame.
Fix the cord with cord bands 󱢽and 󱢾(two locations) on
the side face of the solenoid bracket.

– 5 –
2) Adjusting the open/close amount of the binder
Adjust the open/close amount of the binder with collar
󱣁.
2. Adjustment procedure
1) Adjusting the position of the binder
Perform the adjustment of the position of binder 󱢿
with screws 󱣀.
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the follow-
ing work after turning the power off and ascertaining that the motor is at rest.
󱣀
󱢿
󱣁

– 6 –
III. IN CASE OF USING E23
1. Installing procedure
1) Installing the binder open/close knee switch asm 󰿿
under the table with wood screws 󱀀.
󱀀
󰿿
2) Installing the binder open/close device
Place spacer 󱀁and install binder open/close device
󱀂. Insert air tubes 󱀄into joints 󱀅of binder open/close
knee switch asm. Fix air tube 󱀄with air tube holder
󱀃.
󱀁
󱀂
󱀃
󱀅
󱀄
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the follow-
ing work after turning the power off and ascertaining that the motor is at rest.

– 7 –
3) Installing the binder and the elastic guide
Install binder 󱀇and elastic guide 󱢳.
󱀇
󱢳
4) Installing the air regulator
Install air regulator asm.󱢴under the table with
wood screws 󱢵.
󱢵
󱢴

– 8 –
2. Adjustment procedure
1) Adjusting the position of the binder
Perform the adjustment of the position of binder 󱀇
with screws 󱢶.
󱢶
󱀇
2) Adjusting the open/close amount of the binder
Adjust the open/close amount of the binder with collar
󱢷.
󱢷
3) Adjusting the speed of open/close of the binder
The speed of open/close of binder 󱀇can be changed
with speed controllers 󱢸and 󱢹. When you desire to
change the opening speed of binder 󱀇, loosen the nut
of speed controller 󱢸located on the machine side and
turn the adjustment screw. When you desire to change
the closing speed of binder 󱀇, loosen the nut of speed
controller 󱢹located on the operator side and turn the
adjustment screw. After the adjustment, tighten the nut
of the speed controller.
4) Adjusting the air regulator
1. Insert the air hose to air regulator 󱢺.
2. Use the air pressure at 0.4 to 0.5 MPa (4 to 5 kgf/cm2).
3. Draw up regulator knob 󱢻, turn knob󱢻and adjust the
pointer to 0.4 to 0.5 MPa to adjust the air pressure.
4. After the adjustment, press downward regulator knob
󱢻.
5. When drainage is collected at section A of regulator
󱢺during using, press drain cock 󱢼to discharge the
drainage.
Air hose
󱢺
󱢻
󱢼
A
󱢸
󱢹
WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the follow-
ing work after turning the power off and ascertaining that the motor is at rest.