Adjustment Of The Feed Dog In Longitudinal Direction - JUKI MF-7524 Instruction Manual

18. Adjustment of the feed dog in longitudinal direction

WARNING :
To protect against possible personal injury due to abrupt start of the machine, be sure to start the
following work after turning the power off and ascertaining that the motor is at rest.
Longitudinal position of the feed dog
0.6±0.2mm
❶
❺
A
❸
1.6±0.2mm
❷
❹
– 30 –
1) Position of the main feed dog
It is the standard that the position where the
clearance from the edge of the slot of the throat
plate to the front face of the main feed dog is 0.6 ± 0.2
mm at the position where the main feed dog travels
to the extreme front position (operator's side) when
feed momentum is set to 3.6 mm (maximum).
When fixing setscrew ❷ in the main feed lever,
adjust the clearance from the edge of the slot of the
throat plate to the front face of the main feed dog
to 0.6 ± 0.2 mm when the feed dog travels to the
extreme front position (operator's side), press the
main feed lever to the rocking bar side, and fix it
with setscrew.
When the fixing position of the main feed lever slips
greatly out of position, abnormal noise or abrasion
will be caused.
2) Position of the differential feed dog
It is the standard that the position where the
clearance provided between main feed dog and
differential feed dog is 1.6 ± 0.2 mm when the
differential feed ratio is set to 1 : 1 after adjusting the
position of the main feed dog.
When fixing setscrew ❶ in the differential feed
lever, set the differential feed ratio to 1 : 1, adjust the
clearance provided between the main feed dog and
the differential feed dog to 1.6 ± 0.2 mm, press the
differential feed lever to the rocking bar side, and fix it
with setscrew.
When the fixing position of the differential feed
lever slips greatly out of position, abnormal noise or
abrasion will be caused.
When the adjustment value changes greatly,
feed dog or throat plate will be broken.
Remove rubber plugs ❸ and ❹ without
removing cover ❺. Then, the feed dog can be
adjusted by loosening differential feed lever
setscrew ❶ and main feed lever setscrew ❷.
Cover ❺ is applied with sealant. The sealant
has to be removed when removing cover ❺.
Remove cover ❺ while peeling off the sealant
by tightening an M4 screw in tapped hole A.