6.2.3 Precautions for Fixing the Platen Holder
Design the platen holder to avoid contacting with the thermal head.
If you set the mounting part of the printer and rotation center part of the platen holder to the same
base, accuracy for setting or releasing the platen unit will improve.
It is recommended that the platen unit on which the printer main body is mounted is designed so that
the platen holder is guided by part of the outer case when the platen unit is set into the printer main
body.
Design the rotation center of the rotation system of the door for the platen holder as shown in Figure
6-3. That is, based on the center line which is 10° downward from the horizontal line (which is
horizontal to the printer mounting area), tolerance ±5° from that center line, and 28 mm to 150 mm
away from the center of the platen. The shaded area in the Figure 6-3 is the range of rotation center
of the platen holder.
Parallelism between the positioning holes #1-#2 and the rotation center axis of platen holder should
be 0.2 or less.
Design the platen holder to be strong enough to stand against stress applied during releasing and
setting the platen unit.
Prevent from excessive stress, deformation, and torsion when fixing the platen unit.
When the platen holder, rotation fulcrum of the platen holder, and mounting position of the platen
unit are not proper, engagement of the printer main body and platen unit may be failed, resulting in
printing problems.
Do not use metal material for the platen holder. If using this, the platen unit cannot be mounted.
Design the outer case that holds the platen holder so that the center of the platen unit will be pushed
when setting or releasing the platen unit. When the edge of the platen unit is pushed, a one-sided
lock phenomenon happens, and print defect and/or a paper jam may occur. It is helpful to indicate
which location has to be pushed by showing a symbol on the outer case. Verify the performance
with your actual device.
Do not apply external force continuously toward the direction the platen unit is released. Otherwise,
it may cause paper feed defect and printing troubles during operation.
6-5
