Needle Bar - Brother b831 Service Manual

m NEEDLE BAR (Left and Right) MECHANISM TYPES B835 and B836
(To Stop the Right Side Needle Bar)
1. Move stop lever assembly O to the right side. (Push lever O rises, and the convex part of the back side of stop lever O
attaches to push lever O and stops.)
2. Lever shaft arm O and slide shaft O are moved to the right side via lever shaft arm ©which is attached to stop lever
assembly ©.
3. The slide bearing board assembly © which fits in slide shaft © moves to the right side via collar © and bearing board
spring ©.
4. The pin which is attached to the tipof thrust bearing board assembly © moves sliding blockoperation shaft © to the left
side via moving crank ©.
5. Sliding block assembly © is moved to the rightside viasliding blockoperation lever © whichfits inthe pinscrew affixed
to sliding block operation shaft ©.
6. When the convex part of sliding block assembly © contacts the clutch lever of needle bar connecting stud © attached
to needle bars ©, the clutch in needle bar connecting stud © breaks away from needle bar © and needle bar © stops.
* When the left side needle is caused to stop, the reverse sequence is performed.
(Cancellation of Needle Bar Termination)
When push lever © is pressed, it becomes loosened from the convex part of the back side of stop lever © and is
returned to its original position by lever shaft arm ®.
When stop lever © is returned to the middle position by lever shaft arm spring ©, sliding block assembly © returns to
center position via slide shaft ©, slide bearing board assembly ©, moving crank ©, sliding block operation shaft ©,
sliding block operation lever ®, etc.
The release pin of needle bar connecting stud © is pushed by the convex part of sliding block assembly © and the
clutch fits into needle bars © again.
Needle bar © can be raised and lowered.
1.
2.
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