Xerox Phaser 8500, Service Manual

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2-6 Phaser 8400/8500/8550/8560 Color Printer Service Manual
Theory of Operation
Ink Loader
The Ink Loader consists of four parallel channels with an ink melting element
at the end of each channel. Coil springs exert pressure on four ink sticks to
load one unique color in each channel. When the Printhead requires ink, the
melting element of the appropriate color melts the end of the ink stick. The
melted ink drips into the Printhead ink reservoirs. Sensors in the Ink Loader
alert the customer to install more ink sticks before the printer completely
consumes the current sticks.
If the ink level sensors inside the Printhead detect that the Printhead has run
out of ink, but the ink low/out sensors are not activated, the Control Panel
reports an “Ink Jam” error. The Phaser 8400 features a single Ink-Out sensor,
which activates when there is no ink stick in any of the four ink channels. This
condition activates the sensor flag.
The 8500/8550/8560 features an Ink-Out sensor in each ink stick channel.
Each sensor determines if the individual channel is empty. The sensors also
determine the count of the ink sticks as they pass by the Ink-Out sensor flag.
Ink Loader Door
Ink Stick
Ink Melt Units
Ink Low Sensor
Ink Out Sensor
Printhead
s8500-011