Treadle Unit; Types - Brother Z-8550A Service Manual

12. TREADLE UNIT

12. TREADLE UNIT
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12-1

Types

• Two types of treadle unit are available: a type which controls the automatic presser foot lifter and a type which does not
control it.
• It is possible to switch between the two specifications by <A> Changing the hooking position of the spring (1) inside the
treadle unit; <B> setting DIP switch No. 2; and <C> setting the treadle depression stroke.
SPECIFICATIONS
Operation Does not control the automatic presser foot lifter
<A> [a]
Difference in
spring position
<B> DIP switch No. 2: OFF
DIP switch <When treadle is depressed forward>
setting Presser foot control signal is not output while
treadle is being depressed.
<C> Make the settings in "12-3. Standard settings for
Signal setting treadle depression stroke".
Set the "Neutral position", "Maximum forward
depression position" and "Maximum backward
depression position".
<D> <When depressing forward or depressing backward>
Depression force The depression force hardly changes at all from
the start of depression until the maximum
depression.
<E> <When depressed forward>
Depression Sewing machine starts.
signal <When depressed backward>
Sewing machine starts. (*1)
(*1) The presser foot lifting signal is output while the treadle is being depressed backward. However, if DIP switch No. 1 is
set to OFF, the presser foot lifting signal is not output while the treadle is being depressed backward after the knee
switch has been used to lift the presser foot.
In addition, if memory switch No. 41 is set to "1", the presser foot lifting signal is no longer output while the treadle is
being depressed backward.
103
Treadle unit -G
Z-8550A, 8560A
Controls the automatic presser foot lifter
[b]
（1）
1839M
DIP switch No. 2: ON
<When treadle is depressed forward>
Automatic presser foot lifting signal is output
immediately before the depression force suddenly
changes.
Make the settings in "12-3. Standard settings for
treadle depression stroke".
Set the "Neutral position", "Maximum forward
depression position" and "Maximum backward
depression position".
The modulation position for the depression force
at the first step is set automatically.
<When depressing forward or depressing backward>
The depression force suddenly changes at a point
between the start of depression and the
maximum depression.
<When depressing forward or depressing backward>
Automatic presser foot lifting signal is output
immediately before the depression force suddenly
changes, and the sewing machine starts at the
point after the force suddenly changes.
Treadle unit -H
（1）
1840M