Citizen CL-E720DT, Technical Manual

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Chapter 2 Operating Principles
2-1.
Operation of Each Mechanism
CL-E720DT
2-10
2-1-5. Head Balance Adjustment Mechanism
The major components of the head balance adjustment mechanism are:
(a) Lever Head Balance
(c) Spring Head L/R
(b) Cam Head Balance
The head balance adjustment mechanism eliminates uneven printing density on the media. The
head balance adjustment is accomplished by changing the right side head pressure according to
the media width to be used. To adjust, the blue Media width adjustment dial (Cam Head Balance)
is used. When narrow width media is used, set the dial toward “0” to give weaker pressure. On the
other hand, when wide width media is used, set it 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” act to press the “SA Head” against the “SA 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 “Lever 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 the part “ A ” moves up, the “Spring Head R” is pressed
with weaker force by the “Lever Head Balance” (

), and the right side pressure against the “SA
Head” decreases, resulting in even printing density. You need to adjust 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, turn the Media width adjustment
dial toward “9”. Then the part “
A ” of the “Lever Head Balance” moves down to apply stronger
pressure to the “SA Head”. (Larger number for wider media)
Taward "9"
Spring Head L
(Fixed)
Spring Head R
(Movable)
Cam Head Balance
(Media Width
Adjustment Dial)
SA Head
Media (Narrow width)
SA Head
Media (Wide width)
Taward "0"
Weak
Strong
For narrow media
For wide media
SA Platen
Lever Head
Balance
A
1
2
3