Xerox ColorQube 9303 Series, Service Manual

Page: 1767 / 1812

February 2013
8-73 ColorQube® 9303 Family
Principles of Operation
Waste Tray Lock Solenoid
Refer to Figure 21 .
Figure 21 Waste tray lock solenoid
Ink on Drum (IOD) Monitoring
The IME contains a subsystem that periodically monitors the quality of the image being applied
to the drum. This system automatically detects and corrects a number of parameters in order to
maintain optimum print quality. The IOD is an A size scan bar located at the 6 o'clock position
beneath the drum. This is the same type of scan bar used in the registration / preheat assem-
bly for skew measurement. The primary function of the IOD scanbar is to read special test
prints on the drum and send this information to the controller to maintain alignment and effi-
ciency of the four printheads.
Figure 22 IOD components
As the scan bar is ~ 8.5 inches long and the drum is ~ 12 inches in length, the IOD is mounted
to a rail system that allows movement of the IOD to front and rear positions. This assures the
IOD can properly 'see' the transition area between each of the four printheads.
Figure 22 .
Since the IOD is located beneath the drum, it is possible to contaminate the IOD lens. To help
avoid this, the IOD lens is covered by a plastic shield which remains in place except when the
IOD is actually reading images on the drum.IOD calibrations occur on a regular basis depend-
ing on setting in software, but checks of the printhead alignment are more frequent until the
machine is considered thermally stable. This is to reduce misalignment caused by thermal
shifts to the Staggered Full Width Arrays (SFWAs) and Image Marking Engine (IME). Presently,
when the heads are re-docked, the thermal 'timer' restarts and IOD calibrations will be more
frequent until considered thermally stable. There is no post-adjustment IOD validate process;
adjustments are made and then assumed to be correct.
The IOD has three color outputs (RBG) that are used to achieve the best contrast for the vari-
ous colors printed on the drum.