DFX-8500
Rev. B

2-

6
2.1.3 Platen Gap Adjustment Mechanism
Figure 2-6 shows the platen gap adjustment mechanism. The front and rear carriage guide shafts supporting
the carriage have a vertical section. The rotation of the PG motor is transmitted to the rear carriage guide
shaft through the gears. Counterclockwise rotation of the motor expands the platen gap and clockwise
rotation reduces it.
The encoder plate with equally pitched slits is attached coaxially to the motor axis. When the motor rotates,
the PC sensor detects it and outputs the pulses. Each pulse corresponds to detection of a 0.0025 mm
resolution (horizontal distance). The system range is 0.35 to 0.84 mm.
Platen Assembly
Ribbon Mask Holder
Platen Roller Gear
Platen Gap
Motor
Platen Gap E ncoder Plate
Platen Gap S ensor
Platen Roller Transm ission Gear
SHAFT, CR, GUIDE, REAR
Printhead
CW
CCW
Figure 2-6. Platen Gap Adjustment Mechanism