Service manual

.
REV.-A
2.1.4 Ribbon Advance Mechanism
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The ribbon is held between the ribbon advance roller (ribbon driving gear) and the ribbon pressure roller. ‘“”
i...
When the carriage moves ontheshaft, the timing belt turns the belt driven pulley, andthetorque is transmitted
to the ribbon driving gear through the train of gears. The ribbon driving gear rotates counterclockwise no
matter what direction the carriage moves, because the
planetav gear is used in the gear linkage.
Table 2-2. Ribbon Advance Gear Linkage
I
Direction of Carriage Movement
Gear Linkage
Left to right
Belt driven pulley ● Gear (1) ● Gear (2) ~
(indicated by the black arrow)
Ribbon driving gear
Right to left
Belt driven pulley @ Gear (1) O Gear (3) 0
(indicated by the white arrow)
Gear (4)
0 Ribbon-driving gear
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The ribbon brake spring, attached to the exit slot of the cartridge case, prevents slack in the ribbon and keeps
the ribbon tension at an appropriate level. The ribbon mask prevents the ribbon from brushing against the
paper.
Ribbon
Pressure
Ribbon Advance Roller \
‘-
Ink Ribbon
. /
Mask
Roller
Gear
Brake
ge
Gear (2)
\
#
&*
* + “’
Ribbon
o
Driving Gear ,
0
Figure 2-21. Ribbon Advance Mechanism
2-18