Headlift Mechanism - Intermec EasyCoder 501 XP Service Manual

8.9 Headlift Mecha-
nism
Sensor Arm
Headlift Sensor
Headlift Arm
Eccenter
Printhead Pressure
Grub Screw
(factory-adjustment)
Intermec EasyCoder 501 XP – Service Manual Ed. 4
Description
The headlift mechanism is an integrated part of the print unit. The
mechanism is activated by the green printhead lift lever at the out-
side of the upper part of the print unit. The knob is pressed on
a shaft, which has a disk with an eccentrically fi tted pin on the
inside of the upper, outer gable of the print unit. This pin activates
a fork-shaped pressure adjuster, that via a linkage is connected to
the headlift shaft. The pressure adjuster is fi tted with a spring and
an adjusting screw. Thus, the operator can easily apply more or
less pressure of the printhead against the platen roller depending on
type of media, print method, media thickness, and other circum-
stances.
The headlift shaft is connected to the headlift sensor arm on the
inside of the print unit (see Chapter 8.8.) On the headlift shaft, the
S-shaped headlift arm is also fi tted. At the tip of the headlift arm
is a magnet that engages the printhead bracket. The arm can be
moved along the headlift shaft, so the pressure can be applied later-
ally at the center of the media path, even when narrow media are
used. The hooked fi ngers of the printhead bracket are hung on the
headlift shaft. The concept allows the printhead to align itself verti-
cally to the platen roller, while maintaining a fi xed alignment in the
other two dimensions.
Printhead Lift Lever
Chapter 8 Print Unit
Return Spring
Headlift Shaft
Pressure Adjuster
Linkage
63