Head Balance Adjustment Mechanism - Citizen CL-S6621 Technical Manual

2-1-7. Head Balance Adjustment Mechanism

The major components of the head balance adjustment mechanism are:
(a) Cam Head Balance
(b) Plate Head Balance
The head balance adjustment mechanism is used to eliminate uneven printing density on media.
The head balance adjustment is accomplished by changing the right side head pressure according
to media width to be used. To adjust, the blue Media width adjustment dial ("Cam Head Balance")
is used. When narrow width media is used, the dial should be set toward "0" to give weaker
pressure. While, wide width media is used, it should be set toward "9" to give stronger pressure.
When narrow width media is used (need to give weak pressure):
The "Spring Head L" and "Spring Head R" (2 pcs.) act to press the "SA, Head" against the
"SA2_Platen". For narrow width media, if the same pressure is given on both sides, since no media
exists on the right side of the "SA, Head", the "SA, Head" will slant to the right, resulting in uneven
printing density. The part "A" of the "Plate Head Balance" is pushed against the cam part of the
"Cam Head Balance" by the force of "Spring Head R" and it moves up step by step () as the
Media width adjustment dial is turned toward "0" (). As it moves up, the "Spring Head R" is
pressed with weaker force by the "Plate Head Balance" (), and the right side pressure against
the "SA, Head" decreases, resulting in even printing density. You need to align the dial number
according to the media width to be used. (Smaller number for narrower media)
When wide width media is used (need to give strong pressure):
The same principle applies to wide media. However, in this case, the Media width adjustment dial
should be turned toward "9". Then the part "A" of the "Plate Head Balance" moves down to apply
stronger pressure to the "SA, Head". (Larger number for wider media)
For narrow media
Spring Head L
(Fixed)
SA, Head
Ribbon
Media (Narrow width)
For wide media
SA, Head
Ribbon
Media (Wide width)
(c) Spring Head L/R
Supporting point
Spring Head R
(Movable)
Plate Head
Balance
SA2_Platen
2-15
Toward "0"
Weak
A
Strong
T0ward "9"
Operation of Each Mechanism
Cam Head Balance
(Media Width Adjustment
Dial)
CL-S6621