22
10) Adjusting the height of the feed dog
Turn the pulley to place the feed dog
①
in the highest point. Loosen the feed dog base fastening screw
②
and move the feed
dog base
③
up and down to make the feed dog
①
protrude in parallel from the needle plate upper side
④
by about 1 mm.
(See Figure 33.)
11) Adjusting the needle and hook timing
(1) Fixing the height of the needle bar
Turn the pulley to make the needle bar in the lowest position. Loosen the needle bar holding screw
①
, adjust so that the
needle bar carved sign
②
meets the end of the frame
③
like in Figure 34, then tighten the screw.
(2) Adjusting the timing of hook edge and needle
center crossing
A. First, set the stitch length of (DIAL) KM-757, 757-7,
797, 797-7 types at 2.5mm and KM-757BL, 757BL-7,
797BL, 797BL-7 types at 3.5mm. Adjust the hook gear
fastening screw
①
so that like in Figure 35, the hook
edge falls exactly at the center of the needle center when
the needle bar is raised 2.4mm from its lowest position.
When this is done, the hook edge will be placed at about
1~1.5 mm above from the upper shaft of the needle
thread hole.
B. In case of the 797 series, if the height of the left and
right needles are not the same, or if the Figure 35
situation-where the needle bar is raised 2.4 mm but the
hook edge is not placed about 1~1.5 mm from the upper
shaft of the needle thread hole-is not true, loosen the
fixing screw
②
of Figure 36, pull out the needle holder,
and adjust the needle holder position fixing screw
①
up
and down to set the height of the needle.
Lowest point of needle bar when
using a DP
×
5 needle.
about 1 mm
Cross section of hook edge and
needle center.
Cross section of hook edge and
needle center.
Lowest point of needle bar when
using a DP
×
17 needle.
757 Series
797 Series
Hook
edge
Higher
Needle holder
Lower
[Figure 33]
[Figure 34]
[Figure 35]
[Figure 36]
Содержание KM-757
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