Paper Lift Mechanism - Xerox Phaser 4500 Service Manual

The types of paper that can be automatically detected are as follows:
Type
LETTER SEF
LEGAL 14" SEF
LEGAL 13" SEF
EXECUTIVE SEF
A4 SEF
B5 (JIS) SEF
A5 SEF

Paper Lift Mechanism

The Phaser 4500 printer paper trays utilize a unique mechanical paper lift mechanism
that eliminates the need for paper lift motors. The mechanism consists of a spring-
loaded Bottom Plate Assembly that lifts the paper stack upward to the Paper Feeder
Assembly.
When the tray is removed from the printer, a channel in the Right Tray Guide pushes
the Bottom Lock Gear downward, lowering the Bottom Plate Assembly until it is
locked into place by a spring-loaded Gear Stopper, One-way Lock Gear, and the
Bottom Rack Lock. The Gear Stopper engages the Bottom Lock Gear, and the Bottom
Rack Lock engages the One-way Lock Gear, which prevents the Bottom Plate
Assembly from rising upward.
The Gear Stopper is released from the Bottom Lock Gear when the tray is inserted
into the printer. Once the Gear Stopper releases the Bottom Lock Gear, the Bottom
Rack Lock holds the Bottom Plate Assembly in place. Then, a metal tab located on
the Paper Feeder Assembly presses down on the Bottom Lock Lever. This releases the
Bottom Rack Lock and allows the Bottom Plate Assembly to raise the paper stack
upward until it contacts the Nudger Roller and lifts the feeder assembly.
Once the feeder assembly is lifted by the paper stack, the metal tab no longer contacts
the Lock Lever. As paper is fed from the stack, the feeder assembly gradually lowers.
When the tab contacts the Bottom Lock Lever, the paper stack raises. This process
repeats until the tray is empty.
Theory of Operation
Size (mm × mm)
215.9 × 279.4
215.9 × 355.6
215.9 × 330.2
184.2 × 266.7
210.0 × 297.0
182.0 × 257.0
149.0 × 210.0
2-15