SWF MA-6, Руководство пользователя, Страница: 38 / 76

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8.2.8) Relationship between the take-up lever and the hook
Hook point timing is directly related to thread tension and thread breaks. The following pictures show the
location of hook when the take-up lever starts to move up from the lower dead stop (main shaft rotation angle:
291
°
).
Too small
Too large
1) Hook timing is fast (in the A range)
The hook starts to take the thread from the take-
up lever. Loop is small because the upper thread
is pulled. Stitches are made but stitch tension is
bad. Thread skips occur, where hook fails to go
through the loop.
2) Hook timing is slow (in the B range)
The hook starts to take the loop before the take-
up lever goes up. Thread skips don’t occur, but
thread breaks occur, because the take-up lever
moves faster than the thread coming off the hook.
(A)
(C)
(B)
In normal hook timing, the hook should be in the (C) range.
NOTE