7-11.Synchronizer Adjustment - Brother S-710A Service Manual

7-11. Synchronizer Adjustment
Becomes lower
Needle down position
19 - 25 mm
(2)
Needle up position
<-[][]1>
8 - 10.5 mm
<-[][]3>
10 - 12.5 mm
<-[][]5>
12.5 - 15 mm
(1)
Becomes higher
The synchronizer uses a single element to detect the
0931M
needle up stop position. The needle down single is fixed.
Checking method
1. Turn on the power switch.
2. Stop the machine with the needle in the needle down
position.
Check that the distance from the top of the needle
plate to the bottom edge of the needle set screw is 19
- 25 mm at this time.
3. After the thread is trimmed, stop the machine with the
0741M
needle in the needle up position.
4. Check that the distance from the top of the needle
plate to the tip of the needle is within the value shown
in the illustration in accordance with the machine
model.
Adjusting the needle up stop position.
1. Turn off the power switch.
2. Loosen the screw (1).
3. Move the screw (1) in the direction of rotation of the
machine pulley to raise the needle bar (2) to a higher
stop position.
Move the screw in the other direction to lower the
needle bar stop position.
4. Securely tighten the screw (1).
Note: Do not turn the pulley while the screw (1) is
loosened, otherwise other parts may become
damaged as a result of the looseness.
0932M
SL-710A
7. ADJUSTMENTS
70