Ricoh FT5540 Service Manual page 390

31 August 1989
The bottom plate moves down either when the Down key is pressed or when paper runs out.
When either condition occurs, the flip-flop on the tray main board changes state (all outputs
change from LOW to HIGH or vice versa). Then, two things happen simultaneously: (1) The
timer circuit turns on, causing the LED in the Down key to blink; and (2) SSR100 turns on,
energizing the drive motor to move the tray down.
The tray down sensor is actuated when the bottom plate is fully lowered. This causes the
flip-flop to change back to its original state, which turns off SSR100 and resets the timer circuit.
The LED in the Down key stays on.
Up Operation
Up operation is started by opening and closing the cover while the bottom plate is moving
down or in the down position. The cover safety switch changes the state of the flip-flop to
energize SSR101, which turns on the drive motor to move the tray up. The drive motor stays
on until the paper pushes up the pick-up roller. The actuator on the pick-up roller bracket then
moves out of the upper limit sensor; this again changes the flip-flop's state and the motor
stops.
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