Fujitsu M255XK Customer Engineering Manual page 63

4.5.2 Stepping Motor and Steel Band Replacement
Tools Required: Phillips Screwdriver, M3
Phillips Screwdriver, M2.6
Allen Wrench, 1.5mm
Tweezers
Alcohol and Gauze
Screw Lock Liquid
Exerciser (AVA 409 or equivalent)
Refer to Figure 5-5.
1. Remove the shield cover assembly (item 44).
2. Remove the mounting screws from the main circuit card and lift up the
circuit card (item 43).
3. Unplug all connectors at the main circuit card assembly and remove the card.
4. Remove the screws holding the main circuit card shield plate and remove the
plate (item
23).
5. The head carriage assembly (item 7) and steel band (item 11) are connected by
two fixing plates (A and B). Press fixing plate B (item
12) and the lower head
carriage to relieve the tension, and detach the steel band from fixing plate B.
6. Remove fixing plates, A and B, and the band spring (item 13) from the head
carriage assembly.
7. Remove the mounting screws for the stepping motor pulley (item 3), then
remove the band washer and steel band.
B.
Remove the stepper motor mounting screws.
9. Remove the screw fastening the STM bracket (item 4) - the STM bracket
holds the stepping motor - and then remove the stepping motor.
10. Insert the new stepping motor and hold it in place with its mounting screws.
Note: When replacing the stepping motor, the steel band and the band spring
must also be replaced.
11. Temporarily coil the new steel band to the stepping motor pulley, and install
the stepping motor with the band washer and head carriage.
12. Connect the steel band and head carriage - with band fixing plates A and B -
by reversing the procedures described in steps 5 and 6.
13. Move the head carriage manually, then tighten the steel band mounting screws
to the specified torque. The band must have tension and remain perfectly
straight. Use care to keep the surfaces of the band and pulley clean.
14. Install the main circuit card shield plate, by reversing the procedure described
in step 4.
TS-021-0130B7 ••• 01
4-31