Ricoh FT8680 Service Manual page 94

PAPER FEED 31 July 1995
[B]
[A]
[C]
[E]
[D]
[F]
[G]
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Using the paper feed trigger signal from the main control board the paper
feed clutch [A] turns on and paper feed roller shaft [B] begins to turn. A
one-way clutch drives the paper feed roller [C]. The pick-up roller [D] rotates
via an idler gear. Then, paper feed begins. A one-way clutch allows the
separation roller shaft to drive at high speed in the direction indicated by the
white arrows in the illustration. This is because the high rotational drive ratio
of the drive gear [E] against the feed clutch gear. However, as the separation
roller [F] rotates in contact with the paper feed roller, the separation roller
rotates in the direction of the black arrow.
Paper is fed by the operation described above. The paper feed sensor [G]
senses the paper and the pick-up solenoid activates. The pick-up roller is
then lifted up to its upper position which is out of the paper path.
Simultaneously, the paper feed clutch temporarily turns off.
This process of turning off the paper feed clutch as paper reaches the paper
feed sensor is called pre-registration and is necessary due to the high copy
speed. The paper waits at that point until the proper time, and then the clutch
turns on again to feed the paper to the following transport relay rollers.
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