Thread Nipper Mechanism; Manual Operation; In Thread Trimming - Brother LK3-B430E Mark II Service Manual

3. MECHANICAL DESCRIPTIONS

3-6. Thread nipper mechanism

3-6-1. Manual operation

1. When the presser bar lifter lever q is turned in the direction of the arrow, the presser bar lifter crank w
makes contact with the tension release lever e, pushing the tension release bar r.
2. The end of the tension release bar r pushes the pin t.

3-6-2. In thread trimming

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1. When the thread trimming signal is received, the thread trimmer solenoid operates to push the tension
release driving lever q in the direction of the arrow, and the roller w which is attached to the tension
release driving lever q is positioned on the periphery of the thread trimmer cam e.
2. The tension release cam of the thread trimmer cam e moves the tension release driving lever q in the
direction of the arrow.
3. Tension release lever (U) r, which is engaged with the tension release driving lever q, moves in the
direction of the arrow.
4. The tension release lever (U) r moves the tension release lever y via the tension release rod assy t.
5. The tension release lever y pushes the tension release bar u.
6. The end of the tension release bar u pushes the pin i.
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LK3-B430E Mark II
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