Xerox ColorQube 9303 Series, Руководство по обслуживанию

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February 2013
8-10 ColorQube® 9303 Family
Principles of Operation
Drum Assembly
The drum and enclosed heaters form the key area of the system where imaging takes place.
The drum assembly and transfix system are separate, but interrelated. This section discusses
the drum assembly. The next section goes into more detail on the transfix system.
Figure 14 .
Figure 14 Drum assembly location
Drum Heaters
The drum heater consists of two independent heating sections (front and rear). Each section
contains four heating coils wrapped externally over glass rods. The drum heaters take approx-
imately five minutes to go from room temperature to operating temperature. As the ink reser-
voir takes 20 minutes to reach operating temperature, drum heating is not a limiting factor in
the machine start-up time.
If line voltage is below 180V, the front four coils are configured in series and then placed in par-
allel to the rear four coils. If voltage is greater than 180V, all eight coils are placed in series.
This ensures that the current drawn by the coils remains consistent regardless of the operating
voltage. The automatic re-configuration of the coils is accomplished by a relay located within
the power supply and activated when detected line voltage exceeds 180V.
In the event of a single coil failure, 110 VAC machines will still have one heater section working
(front and rear connected in parallel). However, 220VAC machines would lose all drum heating
in the event of a single coil failure (all coils connected in series).
Drum temperature is critical for print quality and because of this, the temperature is closely
monitored. Since melted ink (132 degrees C which is 270 degrees F) is hotter than the drum
surface (55.5 C or 139 F) when applied, long, high area coverage print runs may raise the tem-
perature of the drum to the point where no drum heating is required and eventually the drum
cooling fan cannot maintain the correct drum operating temperature. System software should
slow the machine down or inhibit printing temporarily while the drum cools to the proper tem-
perature range. This should only happen with jobs of >150% coverage and > 350 copies.
The drum heating AC circuits are routed through the thermal cutout board that forms part of the
registration / preheat assembly. The thermal cutout board sits directly above the drum and
should the drum overheat, the thermal cutouts should permanently open and remove power
from the drum heater circuits. Drum Heaters also are inhibited unless the drum is turning.
Drum Encoder
The drum encoder helps to track runout variations in the drum surface which can result in a dis-
tance variance between the drum and the printheads. The encoder keeps track of the home
position of the encoder and the IOD reads the drum distance at six degree intervals. This infor-
mation is used by the system to help set printhead 'Y' direction compensation to properly set
the jet firing timing. Drum home position may also be used in fault tolerance mode if it is known
there is a defect in the drum surface. The encoder signal can be used to prevent printing in the
defect area whenever possible.
Figure 15 .
Figure 15 Drum encoder