12.4 Reflecting Light Barrier for Flap Scanning (745-22 and 745-24)
The recognition of the seam beginning and seam end occurs via the
reflecting light barrier b44 when sewing with flap.
Presetting:
–
Set the correction values for seam beginning (NA) and seam end
(NE) to the median value 50 (no correction) (see Short Description
Microcontrol).
–
The clearance between the forward-lying needles and the point of
contact of the invisible infra-red beam must be 55 mm.
With the folding plates closed the infra-red beam must hit the
center of the reflecting foil 1.
Checking the alignment
The alignment of the infra-red reflecting light barrier (b44) is made in
program P55:
–
Turn the main switch on.
–
Set the "Program" switch to "55".
–
Press the "STOP" key
The program is activated.
–
The first line of the display shows the switching status of the
reflecting light barrier:
Reflection:
"+B44"
Interruption:
"- B44"
–
Place a piece of reflecting foil 6 (in the accessories pack) 55 mm in
front of the needles.
–
The light barrier should recognize the reflecting foil precisely at
this point. The first line of the display must show " +B44".
–
If necessary, correct the alignment.
–
Scan the reflecting foil 1 by pushing the transport carriage back
and forth. The first line of the display must show "+B44" along the
whole length.
–
If the display changes to "-B44":
Align the reflecting light barrier exactly over the reflecting foil 1.
Set the transport clamp parallel to the carriage path.
Correcting the alignment
Caution Risk of Injury !
Turn the main switch off.
Align the reflecting light barrier only with the main switch turned off.
–
Loosen screws 7.
–
Align the light barrier mountings 3 in the direction of transport
above the underlying reflecting foil 6.
–
Tighten screws 7 again.
–
Screw setting screw 4 into the mounting piece 2 so that it extends
approx. 4 mm on the other side.
Setting screw 4 serves for the sideways fine adjustment of the
reflecting light barrier b44.
–
Loosen screw 5 slightly.
–
Align the reflecting light barrier b44 sideways precisely over the
middle of the reflecting foil 1.
–
Tighten screw 5 again.
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