Paper Picking; Figure 5-9 Paper Picking - Tektronix Phaser 550 Service Manual

5
Theory of Operation

Paper picking

5-12 Phaser 550 Color Printer
A sheet of paper (or transparency film) is picked when a pair of cam-shaped
rollers, driven by the paper-feed motor, rotate and force a sheet of paper from
the stack into a pair of intermediate rollers. The pick roller only rotates one
revolution which is enough to push the sheet of paper into the intermediate
rollers.
The intermediate rollers advance the sheet of paper to the aligning rollers. The
paper is pushed against the clutch-driven aligning rollers slightly without them
rotating to create a slight buckle in the paper, which aligns the sheet of paper
parallel to the paper path. At this point, the paper remains stationary (since the
aligning roller's clutch is not yet energized) until the image is ready to be
printed on the paper. The aligning sensor detects whether the sheet of paper
arrived at the aligning rollers after being properly picked and traveling through
the intermediate rollers.
Path for
manually
fed paper
Intermediate
rollers

Figure 5-9 Paper picking

A similar pick and feed operation takes place in the optional lower tray
assembly to pick and feed the sheet into the printer's intermediate rollers.
Aligning
roller
Aligning
sensor
Pick rollers
Path for paper from
optional Lower Tray Assembly
9013-12