Thread Breakage Detection Mechanism - Brother LH4-B800E Service Manual

1-7. Thread breakage detection mechanism

1. The cutter bar fixed plate assembly q and the thread guide w are secure to the thread breakage perceiving shaft
e. When a thread breakage occurs, the cutter bar fixed plate assembly q drop by its own weight and moves the
thread guide w in the direction of the arrow.
2. When the sensor r detects the cutter bar fixed plate assembly q, the sewing machine stops and the cutter is
prevented from dropping.
e
q
r
LH4-B800E
1. MECHANISM DESCRIPTION
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