Ricoh A-P4, Service Manual

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When the paper tray runs out of paper, the paper end feeler drops into the cutout [C] in the tray bottom
plate and the paper end sensor is activated.
Paper Registration
The registration drive roller [A] and idle roller [B] correct the skew of the paper to ensure that the leading
edge of the paper is positioned correctly at the drum. The paper feed/development motor [C] drives the
registration mechanism.
The registration sensor [D] is just before the registration rollers. When the leading edge activates the reg-
istration sensor, the registration clutch is switched off and the registration rollers stop turning. However, the
relay clutch [E] remains on slightly longer. This delay allows more time for the paper to press against the
registration rollers and buckle slightly to correct any skew. The registration sensor also detects misfeeds.
Next, the registration clutch [F] and the relay clutch turn on at the correct time to align the paper with the
image on the drum. The registration rollers then feed the paper to the image transfer section.
Two new dust blades have been added around the registration roller. The idle roller dust blade [G] cleans
the registration idle roller. This dust blade has a small dust box that collects paper dust that must be emptied
periodically.
The registration roller dust blade [H] cleans the registration roller. For details about how to remove and
clean these new parts, see Section “3 Replacement and Adjustment”.
Paper Size Detection
The paper size switch includes four microswitches. Actuators behind the paper size dial actuate the sensors.
Paper Feed
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