Brother 434C Sewing Machine User Manual


 
5. ADJUSTMENT
-25. Adjusting the needle up stop position
KE-430B, 430C series
129
Feed mechanism operates.
Material
Feed mechanism stops
2576Q 3502Q
Lo
osen the screw (5) (at the U side on the pulley), and turn the pulley (1) so that the mark (2) on the pulley is
inside the mark (4) of the belt cover (3). The pulley (1) will stop more slowly if the screw (5) is moved counter to
the normal direction of rotation, and will stop more quickly if the screw (5) is moved in the normal direction of
rotation.
The standard position is when the needle bar is lowered approximately 5.5 mm from its highest position.
Timing between the needle and the feed mechanism is adjusted so that the feed mechanism starts operating
after the needle comes out of the material sewn, and stops before the needle penetrates the material.
Note:
• The screw (6) at the “D” mark is an adjusting screw for the needle down detection function and is adjusted
to match the feed timing, so it should not be loosened.
• The screw (7) is a screw for detecting the machine stop position, and should not be loosened.
-26. Adjusting the tension of the upper shaft timing belt
3576Q
1. Loosen the three bolts (1).
2. Turn the bolt (3) in the tightening direction to
adjust the position of the motor bracket (4) so
that there is approximately 2.5–3.0 mm of
deflection in the upper shaft timing belt (2) when
the middle of the belt is pressed with a force of
10 N.
Approx. 2.5 - 3.0mm