Ricoh PCU10, Service Training Manual

Page: 41 / 195

2.1.4 Paper end and set detection
Paper end detecting mechanism
Tray No. 1
The paper end sensor of tray 1 (a reflective
photosensor) detects paper end, the tray lowers, and a
display in red letters appears at the guidance display.
Tray No.2 and 3
Due to the difference of the paper transportation length,
the original feed timing in the ADF is faster than the
paper feed timing for trays 2 and 3. This means that
ADF operation cannot be stopped by the paper end
detection during continuous copying.
When the volume of paper becomes small,
approximately 50
±
45 sheets, paper end is detected.
For limitless paper feed, if the paper size is the same,
paper feed starts from the next tray. If limitless paper
feed is not selected, paper feed stops when paper end is
detected.
When paper end is detected, the tray lowers and a
display appears in red letters on the guidance display.
Paper set detecting mechanism
Tray No. 1
Using the paper end detecting mechanism, the CPU
senses that there is no paper when the tray 1 is set in
place. In that case, the tray motor does not operate.
Tray No. 2 and 3
Since the paper end detecting mechanism can not be
used as a paper set detection for these trays, each of
the tray 2 and 3 has the paper set sensor. When the
CPU knows through this sensor that there is no paper,
the tray motor does not operate.
Paper set sensor (for trays 2 and 3)
1 July 1994 Paper Feed
2-5