Ricoh FW780 Service Manual - Page 238

EXPOSURE 2.3 EXPOSURE 2.3.2 PAPER AND ORIGINAL FEED (A252 ONLY) [D] [B] [C] [G] [H] 26 mm [F] [I] [J] [K] 15 mm J: Original Rear Roller K: Original Rear Sensor [A] [E] A252D500.WMF A252D501.WMF In this machine (A252 copier), first, the leading edge [A] of the original is inserted into the original table and the original is delivered to the appropriate start position. Then the original is switched back while it is being scanned. Therefore, the original is scanned from the trailing edge to the leading edge. When an original is placed on the original table, it activates the original entrance sensor [B]. The main motor starts rotating and the quenching lamp, development bias, and PTL begin. Then, the exposure lamp turns on. To ensure correct original feeding (especially for a thin original), the original is returned toward the operator side (300 ms) before the original feed. Thus the original will be fed evenly by each roller on the original entrance roller [C]. 4 seconds after the original entrance sensor is activated, the original feed motor starts rotating 200 mm/s to turn the original entrance rollers [C] and the original rear rollers [J]. The original is delivered to the original feed start position [D]. The 4 second delay allows time for the operator to align the trailing edge (non-operator side) against the first set of the rollers (to prevent skewing). A251/A252 2-2 SM