Ribbon Feed Mechanism And Operation - Atari 1025 Field Service Manual

RIBBON FEED
MECHANISM AND
OPERATION
RIBBON FEED
MECHANISM
The
ribbon feed
mechanism
consists of the following:
•
Ribbon
drive gear
•
Ribbon
gear
•
Ribbon
spool gear
•
Ribbon change
lever
• Eyelet detector
lever
•
Ribbon
bracket
The
space
pulse
motor
used
to
drive the carriage
also provides the power
to
feed the
ribbon.
RIBBON FEED
OPERATION
When
the space pulse motor's drive
belt runs counter-clockwise,
it
engages
the central
ribbon gear with the ribbon spool gear
and winds
the ribbon,
while the opposite ribbon
spool turns
freely.
When
the space
pulse
motor
turns clockwise and the
print
head
moves
from
left to right,
the central ribbon gear disengages
and remains disengaged
until the
motor
direction reverses.
The
eyelet detector
lever indicates the direction
in
which
the ribbon feeds.
When
this
lever
is
pushed
to
the
left,
the ribbon feeds
left,
and
vice versa.
When
the ribbon
is
nearly run
out,
the ribbon eyelet pushes the eyelet detector lever
in
the opposite
direction.
The
ribbon then feeds
to
the
right
in
the
same
fashion as described
above.
(See Figures 1-3 and
1-4 below).
Figure
1-3. Ribbon Feed
to
Left
1-4
Atari 1025 Printer
Field Service Manual