Toshiba 4580, Руководство по обслуживанию

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6570/5570 PAPER FEED SYSTEM 9 - 4 Mar. 1999 © TOSHIBA TEC
9.1.3 Detection of the remaining amount of paper
■
Paper-empty detection
•
When the LCF or the cassette has run out of paper, the LCF door is opened, or the cassette is
removed, the “ADD PAPER” symbol
↓
lights on the display panel on the copier.
■
Detection principle
•
When the cassette is selected and after the START button is depressed, the tray is lifted to the feed
position and makes contact with the feed rollers. The Tray-Up Switch is directly connected to the feed
roller assembly and thus it is actuated moments after the feed rollers make contact with the paper.
After the completion of every paper-feed operation (per tray unit), the same unit is repositioned to the
down position and is removed from the feed roller assembly and thus, from the Tray-Up Switch. The
PFC measures the period of time that it takes the Tray-Up Switch of each cassette to be actuated
(turned ON) for every time that it is used. It does this for every paper feeding operation. Obviously,
the Paper Feed Control Circuit (PFC) acknowledges the differences in the duration of time it takes for
the Tray-Up Switch to actuate during every print cycle and makes calculations based on time differ-
ences every time the tray is used. These calculations are translated into icons depicting one of five
displays on the LCD panel. See illustrations below.
PFP cassette
N Status Display
N=0 Empty
1
<
=
N
<
=
125 Paper remaining
125<N
<
=
250 Paper remaining
250<N
<
=
375 Paper remaining
375<N Paper remaining
LCF
N Status Display
N=0 Empty
1
<
=
N
<
=
500 Paper remaining
500<N
<
=
1000 Paper remaining
1000<N
<
=
2000 Paper remaining
2000<N Paper remaining