HP LaserJet II Serie Manual De Instrucciones página 199

HP 33440/HP 33449 COMBINED SERVICE MANUAL
Paper Feed Mechanical Checks
The purpose of solenoid SL301 is to allow the Paper Pickup Roller to pick one sheet of paper from
either the paper tray or the mwud feed tray and advance the paper to the Registration Rollers.
Since the Registration RoUers are not turning at this time, the paper will be bowed slightiy as it
enters the &gistration Rollers (see Figure 7-11).
Paper pickup operation is initiated by the DC Controller's main microprocessor. The Cassette
Pickup Drive (CP~) signal from the microprocessor energizes the pickup solenoid (SL301) (see
FiWre 7-10). The energizing of the solenoid engages the paper pickup clutch. The enga@ng of the
clutch allows the Paper Pickup hller to make one rotition, picking up one sheet of paper and
advancing the paper to the Regitimtion Rollers. The Separation Pad acts to prevent more than
one page being advanced to the Registration Rollers should more than one piece of paper leave the
input tray.
HINT
If an ovetidled paper tray results in subsequent paper jams, the Feed Roller
Assembly has probably suffered permanent damage and will require replacement.
Pick-up
Roller
Figure 7-10. Feed Roller Assembly Operation
Registration Rollers
Paper (awed)
I
o-~o
Pickup Roller
o
0
0
Separation Pad
c=
Paper Stack
Figure 7-11. Paper
Positioned in the
Regis&ation Rollers
7-35