Points Of Adjusting And Assembling The Thread Take-Up And The Needle Bar Mechanism - JUKI DDL-9000 Engineer's Manual

3-29 Points of adjusting and assembling the thread take-up and the needle bar mechanism

[Thread take-up]
* It is not necessary to lubricate to the thread take-up since the grease-sealed ball bearing is used.
Defective position of the thread take-up crank largely affects the durability of thread take-up and noise occurrence.
Adjust the thread take-up crank shaft in the following procedure.
1) Loosen setscrew (1) in the thread take-up crank shaft.
2) Remove the thrust of thread take-up crank (3) with thread take-
up crank shaft thrust collar (2).
3) Turn the handwheel two to three times by hand to fit the position
of the thread take-up crank shaft.
4) Further, move the top end of the thread take-up to the right and
left with a finger at the position near the upper dead point of the
thread take-up, and check that there is a play.
5) Turn the handwheel again by hand at the position near the center
of the play, and securely tighten setscrew (1) in the crank shaft
in this state.
[Needle bar]
* Forced lubrication and reflux function, different from the existing sewing machines, is not provided in the face
plate section.
For SS and SH types, minimized amount of oil is supplied to the needle bar with oil wick since the maximum
number of revolution is high.
Pay attention to the following matters in order to maintain the reliability of the needle bar.
(SS, SH)
1) Check that oil wick located at the top of the oil wick support
securely comes in contact with the needle bar at the position of
approximately 5 mm below the needle bar upper metal and when
it does not, adjust the position of the oil wick support.
2) When centering of needle bar upper and lower metals is not
properly performed, seizure will result.
Touch with fingers the periphery of the needle bar lower metal
when running the sewing machine continuously for approximately
30 seconds at the speed of around 4,000 rpm, and when you
feel abnormal exothermic, there is a possibility of defective
centering.
Correct the metal or replace it with a new one.
(DS, DF)
Different from SS and SH, the machine is not provided with the function of lubrication with oil wick.
Special grease is enclosed inside of the needle bar lower metal, and maintenance is not required until the sewing
machine runs at the speed of 4,000 rpm.
When it is compelled to replace the needle bar, however, enclose the seaparately-available exclusive grease
inside of the needle bar lower metal.
Temperature will slightly rise at the beginning of enclosing grease, and return to the normal condition when
making the machine run idle for 2 to 3 minutes at the initial stage and dirty grease of initial abration is discharged.
In this case, perform break-in operation for a few minutes, and use the machine from the state that grease is not
discharged.
* For both SS and DS, apply a rather large quantity of the exclusive grease (23640204) to the groove of the
needle bar roller.
− 34 −
(3)
(2)
(1)