RICOH AFICIO 850
Manual de Servicio

PAPER FEED

22 October 1999

Paper Lift/Remaining Paper Detection
The machine detects when the 1st tray has been placed in the machine by monitoring the tray set signal through the connector.

[E] [E]

[A] [J] [B] [H] [M] [F] [K] [D] [I] [N] [C]

[L]

[G]
A294D710.WMF

When the machine detects that the 1st paper tray is set in the machine, the right 1st tray paper sensor [N] (under the tray) checks whether there is paper in the right tandem tray. NOTE: The right half of the tray holds up to 1,000 sheets. So, if the right 1st tray paper sensor was not present and the tray was empty, the bottom plate would have to lift up fully until the paper end sensor at the top of the tray detected that there was no paper, and this would waste several seconds. If paper is detected, the lift motor [A] rotates and the coupling gear [B] on the tray lift motor engages the pin [C] of the lift shaft [D]. The tray wires [E] are fixed in the slots [F] at the ends of the tray support rods [G, H]. When the lift motor rotates clockwise, the tray support rods and the tray bottom plate [I] move upward. The tray goes up until the top paper pushes up the pick-up roller and the lift sensor in the 1st feed unit is activated, and the paper end sensor at the top of the tray is deactivated. When the actuator [K] on the front end of the right support rod [G] activates the paper height sensors [J], the remaining paper capacity is detected (4 levels). When removing the tray, the coupling gear [B] separates from the pin [C], so that the tray bottom plate moves downward. The tray lowers until the actuator activates the tray down sensor [L]. The damper [M] lets the tray bottom plate drop down slowly.
2-84