Sharp AL-2051 Service Manual page 40

(1) Cassette paper feed operation
1) The figure below shows the positions of the pick-up roller, the
paper feed clutch sleeve, and the paper feed latch in the initial
state without pressing the Start key after lighting the ready
lamp.
The paper feed latch is in contact with the projection of the
clutch sleeve.
2) When the Start key is pressed, the main drive motor starts
rotating to drive each drive gear.
The pick-up drive gear also is driven at that time. Since, how-
ever, the paper feed latch is in contact with the projection of the
clutch sleeve, rotation of the drive gear is not transmitted to the
pick-up roller, which does not rotate therefore.
PFS
OFF
3) After about 0.1 sec from when the main motor start rotating, the
tray paper feed solenoid (PFS) turns on for a moment.
This disengages the paper feed latch from the projection of the
clutch sleeve, transmitting rotation of the pick-up drive gear to
the paper feed roller shaft, rotating the pick-up roller to feed the
paper.
PFS
OFF
4) After more than half rotation of the pick-up roller, the paper feed
latch is brought in contact with a notch on the clutch sleeve,
stopping rotation of the pick-up roller.
5) At this time, the paper is fed passed the paper entry detection
RRS
6) To release the resist roller, the tray paper feed solenoid and the
OFF
7) After the resist roller starts rotating, the paper is passed through
RRS
OFF
8) The paper separated from the drum is passed through the fus-
AL-2051 OPERATIONAL DESCRIPTIONS 7 - 5
switch (PPD1), and detected by it. After about 0.15 sec from
detection of paper by PPD1, the tray paper feed solenoid (PFS)
turns on so that the clutch sleeve projection comes into contact
with the paper feed latch to stop the pick-up roller. Then the
pick-up roller rotates for about 0.15 sec so that the lead edge of
the paper is evenly pressed on the resist roller, preventing
against skew feeding.
PFS
ON
resist solenoid are turned on by the paper start signal to disen-
gage the resist start latch from the clutch sleeve, transmitting
rotation of the resist drive gear to the resist roller shaft. Thus the
paper is transported by the resist roller.
the pre-transfer guide to the transfer section. Images are trans-
ferred on the paper, which is separated from the OPC drum by
the drum curve and the separation section.
PFS
OFF
ing paper guide, the heat roller (fusing section), POD (paper out
detector) to the copy tray.
RRS
OFF
RRS
ON