Citizen CLP-621 Technical Manual page 119

(2) Ribbon slant elimination adjustment (For service personnel)
(2-1) Tension base adjust cam position adjustment (For service personnel)
This adjustment is required in the following cases:
• If the parallelism reference for the user adjustable range needs to be changed. (This
adjustment will be required if ribbon wrinkle cannot be removed with the Ribbon
Left-Right Balance Adjustment Knobs (Front/Rear).)
• Tension Base Adjust Cam is replaced or reassembled.
By adjusting the Tension Base Adjust Cam, the parallelism of the Ribbon Sensor F/R Unit
(movable part) against the unit base (fixed part) is changed. The user adjustment using the
Left-Right Balance Adjustment Knobs (Front/Rear) is done based on the new parallelism
reference.
Note: The Tension Base Adjust Cam is adjusted at the factory before shipping. Therefore,
it may be off-center when shipped.
Adjustment procedure:
1. Remove the Ribbon Tension Adjustment Cover from the Ribbon Sensor F/R Unit.
2. Loosen 2 screws "A".
3. Loosen the screw "B", and turn the Tension Base Adjust Cam clockwise or
counterclockwise. The parallelism of the Ribbon Sensor F/R Unit against the base is
changed.
4. Tighten screws "B" and "A" (2 pcs.).
Shifting the Ribbon Sensor F Unit (Viewing from the front side)
Left side ribbon wrinkles cannot
be eliminated by user adjustment.
Cam, Base
Tension Adjust
A B
CW
Shifting the Ribbon Sensor R Unit (Viewing from the rear side)
Left* 1 side ribbon wrinkles cannot
be eliminated by user adjustment.
Supporting point
A
CW
*1: Shows the direction viewing from the rear side.
CW: Clockwise
CCW: Counterclockwise
Mechanical center
(SA1, Ribbon Unit Base Plate)
A
Supporting point
Mechanical center
B
A
Base
Center
Unit, Ribbon Sensor F
Base
Center
Unit, Ribbon Sensor F
3-47
3-6. Adjustments
Right side ribbon wrinkles cannot
be eliminated by user adjustment.
CCW
Right* 1 side ribbon wrinkles cannot
be eliminated by user adjustment.
CCW
CLP-621 & CLP-631