S-7300A
3. INSTALLATION
15
2. Test operation
1.
Check that the machine sews at low speed when
the treadle (1) is gently pressed to position (B).
2.
Then check that it sews at high speed when the treadle
(1) is gently pressed to position (C).
3.
After pressing the treadle (1) forward, check
that the needle is lowered to the top of the needle plate
when the treadle (1) is returned to the neutral position
(A). (when needle down stopping has been set.)
4.
If the treadle (1) is pressed to position (D), thread
trimming is carried out and the needle then rises above
the needle plate and stops.
3-6. Adjusting the treadle
<Forward depression sensitivity adjustment>
If the machine starts running at low speed when your foot is
simply resting on the treadle, or if the treadle pressure is felt
to be too weak, adjust the position (a to c) at which the
treadle spring (1) is hooked onto the treadle lever (2).
* a is the weakest position, and it becomes gradually
stronger at b, c and d respectively.
<Backward depression sensitivity adjustment>
1. Loosen the nut (3) and turn the bolt (4).
* When the bolt (4) is tightened, the treadle operation
becomes heavier, and when it is loosened, the operation
becomes lighter.
2. Tighten the nut (3).
< Adjusting the treadle stroke >
Remove the nut (5), and then move the connecting rod joint
(6) from the position in figure A to the position in figure B.
The treadle stroke will then be increased by approximately
27 %.
At this time, the treadle forward and backward depression
sensitivity will change, so readjust if necessary.
3648M
2117M
0939D
0940D
