Printing And Ribbon Feed Mechanism - Citizen CL-S6621 Technical Manual

Operation of Each Mechanism

2-1-4. Printing and Ribbon Feed Mechanism

The major components of the printing and ribbon feed mechanism are:
(a) SA, Head
(b) SA Ribbon Motor F/R
(c) Ribbon gear train
Ink ribbon is set to the printer using the ribbon holders. Ribbon is supplied from the supply reel and
is taken up by the take-up reel with adequate ribbon tension, via the "SA, Ribbon Tension Shaft R"
and "SA, Ribbon Tension Shaft F". The "SA, Ribbon Tension Shaft F/R" is always pushed outward
by the internal springs, and, when ribbon slacks, it moves outward. When ribbon tightens, it moves
inward. (Refer to the figures on the later pages.)
The same ribbon sensor is installed on the front and rear sides. The ribbon sensor on the front side
is used to detect the position of the "SA, Ribbon Tension Shaft F" (i.e., the ribbon tension on the
front side). While, the ribbon sensor on the rear side is used to detect the position of the "SA,
Ribbon Tension Shaft R" (i.e., the ribbon tension on the rear side).
The ribbon sensor on the front side is also used to detect a ribbon running condition, and that on
the rear side is used to detect the ribbon end.
On the front side, the "SA Ribbon Motor F" turns to take up ribbon. On the rear side, the "SA
Ribbon Motor R" turns to supply ribbon, while applying adequate back tension to ribbon to
eliminate ribbon slack.
SA Ribbon Motor F
Gear Reduction Ribbon 1
Gear Reduction Ribbon 2
Gear Reduction Ribbon 3
SA, Ribbon Tension
Shaft F
Ribbon
SA2_Platen
[Front]
Printing:
When printing with ink ribbon, ink on the ribbon is melted by the heated thermal element of the "SA,
Head" and is transferred on the media surface.
CL-S6621
(d) SA, Ribbon Tension Shaft F/R
(e) SA, Ribbon Sensor (Front/Rear)
Take-up Side
Gear Ribbon Shaft F
Gear Idle Ribbon
Thermal Head
Supply Side
Gear Reduction Ribbon 1
SA Ribbon Motor R
Gear Reduction Ribbon 2
SA, Ribbon Tension
Shaft R
Media
2-10
Gear Ribbon Shaft R
Gear Idle Ribbon
Gear Reduction Ribbon 3