Thermal Printhead - Sharp SX 1075 Service Maintenance Manual

THERMAL PRINTHEAD

TESTING
WARNING
Always remove electrical power from the
SX prior to performing any maintenance
on the machine.
1. Problems with the printhead are indicated by
poor image quality, unreadable bar codes, or
voids in the print (repeated areas unprinted on
the bag). Visually inspect the printhead for
scratches or buildup of ribbon or film materials.
Clean the printhead
thoroughly using a soft, lint-free cloth and
isopropyl alcohol. If cleaning does not produce
desired results,
replacement. (Note: Refer to Appendix 1,
"Protecting Your Printhead" located in the back
of this manual for tips on getting the longest life
out of a thermal printhead.)
ADJUSTMENT
Small adjustments can be made to fine-tune the
print quality by moving the printhead adjustment
screws slightly (Figure 3-258). This moves the print
contact area on the platen roller to optimize the
print quality. Make small adjustments, and cycle
machine to test results. Continue until print quality
is best.
Printhead
Adjustment
Figure 3-258. Printhead Adjustment Screws
SX™
Service and Maintenance Manual
PRINTHEAD CRADLE ASSEMBLY
and platen
the printhead needs
Screws
SECTION 3 – COMPONENT REPAIR
1. With power removed, open the cradle cover
and release the cradle latch to expose the
printhead. Remove any ribbon from the print
area.
2. Locate the two screws shown in (Figure 3-259).
Remove these
printhead.
removed, the printhead will only be held by the
cables.
roller
Figure 3-259. Printhead Mounting Screws
3. Unplug the power and data cables from the
back of the printhead.
This procedure deals with handling parts
susceptible
discharge (ESD). Use static control precautions
while servicing this equipment.
4. Install the cables into the new printhead,
making certain the cable ends are fully inserted
into the receptacles.
5. Install the new printhead onto the printhead
pressure assembly.
with locating pins on the pressure assembly to
fully seat the printhead into the correct position.
Once in position, insert the two screws and
secure.
6. Rethread the ribbon according to the threading
diagram located on the top panel of the side
guard.
3-102
REPLACEMENT
two screws
Note: Once these screws are
Printhead Mounting Screws
WARNING
to damage from
The printhead will align
960714-02B © 2007 I2407
to free the
electrostatic