Upper Thread Trimmer Mechanism - Brother LH4-B800E Service Manual

1. MECHANISM DESCRIPTION

1-10. Upper thread trimmer mechanism

Upper thread trimmer mechanism operating sequence
(1) Sewing starts (machine
starts)
(2) After 1.5--2.5 mm of feed, the upper
thread scissors gradually start to
open.
(3) After approximately 4.6 mm of feed,
the upper thread scissors are fully
pen.
1 - 12
(8) The presser foot drops.
(4) (3)
(2) (1) (8)
(5)
(7)
(4) Sewing ends.
LH4-B800E
(7) The upper thread scissors re-
tract and the presser foot lifts.
Presser foot
drops
Presser foot
lifts
(6) The upper thread is
clamped and cut.
(6)
(5) The upper thread scis-
sors move forward.