Datasheet

74 Chapter 1
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Hardware
FIGURE 1.26 The EP laser scanning assembly (side view and simplified top view)
Mirror
Laser beam
Laser
assembly
EP drum
Rotating mirror
Direction of
rotation
Laser scanning
assembly
Laser
beam
Fixed
mirror
SIDE VIEW
Paper Transport Assembly Moves the paper through the printer. The paper transport
assembly consists of a motor and several rubberized rollers. These rollers are operated by
an electronic stepper motor. See Figure 1.27 for an example.
FIGURE 1.27 Paper transport rollers
Feed roller
Exit rollers
Fuser rollers
Registration rollers
Transfer Corona Applies a uniform positive charge (about +600V) to the paper. When
the paper rotates past the drum, the toner jumps off the drum and onto the paper. Then the
paper passes through a static eliminator that removes the positive charge from it. (See Fig-
ure 1.28.) Some printers use a transfer corona wire; others use a transfer corona roller.
High-Voltage Power Supply (HVPS) Delivers the high voltages needed to make the print-
ing process happen. It converts ordinary 120V household AC current into high-DC voltages
used to energize the primary and transfer corona wires (discussed later).
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