Needle Bar Top Dead Center - Brother PR655 Service Manual

Adjustment
[Standard]
When the needle bar is in highest position, there should not be clearance between the top dead center plate and the
cushion rubber. And the cushion rubber should be compressed slightly (approx. 0.3 mm).
[Adjustment]
1. Start the test mode and select [#12: Needle threader] under [MAIN
BOARD TEST MODE].
2. Press the [L-R position] and the standard needle bar for adjustment
will be selected automatically. The needle bar case unit will move to
the left and right.
3. Turn the pulley by hand to move the needle bar to the top point.
4. Loosen the 2 screws 1 of the top dead center plate.
5. Push the top dead center plate towards the needle bar (downward) so
that the cushion rubber is compressed slightly, and tighten the 2
screws 1 to secure the dead center plate.
6. Check the needle threader.
*Key point
• When needing the adjustment of the needle threader, make
adjustments following the guidelines in section "4-27 Needle
threader (up/down)" and "4-29 Needle threader (left/right)".
7. Move the needle bar to the top point again, check that the all top
dead center plates of the needle bars are the same height.
*Key point
• When differing the height of the
adjustments of steps 4 to 5 above.
1
1
Cushion rubber

Needle bar top dead center

top dead center plate
Screw, Bind
M4X6
Top dead center plate
4 - 26
, make
The height of the
top dead center
plates are same.