Panasonic FP-D250 User Manual page 40

2) Operation of sheet bypass paper feed unit
(1) Paper feed operation
• After choosing the sheet bypass tray and pressing the start key, the main motor
is energized. The main motor drives to the transmission gears via the respective
driving gears.
Consequently, drive is transmitted to the registration roller gear of the sheet
bypass paper feed unit.
The revolution of the registration roller gear is transmitted to the sheet bypass
clutch gear via an idler gear.
• The sheet bypass transfer roller to lower and contact the paper in the tray,
while releasing the stopper at the same time.
• Turning on the sheet bypass clutch, the transfer roller (which touches the paper)
and the paper feed roller rotate to transfer the paper towards the registration
roller.
• On the way to the registration roller, the paper is detected by the paper pass
sensor located just before the registration roller.
After a specified time, the sheet bypass clutch turns off, which stops the sheet
bypass feed rollers.
When the sheet bypass solenoid turns off, the transfer roller is lifted up.
The paper is held in place by the registration roller.
• After a specified time following the optics system start, the lamp unit home
position sensor detects the passing of the optics system (full speed unit), the
registration roller clutch is turned ON and the registration roller rotates.
Accordingly the paper is fed into the image transfer area and the registration of
original and copy paper is achieved.
(2) Double Feed Prevention
• The double feed prevention roller contacts the sheet bypass paper feed roller
pinching the paper at a specific pressure.
The rotating force of the double feed prevention roller is under specific torque,
when multiple sheets are fed, the double feed prevention roller rotates in the
reverse direction feeding the bottom paper back into the tray.
(3) Paper Retry
• The paper pass sensor checks the paper feed from the tray.
If the paper is not detected by the paper pass sensor within a specified time
the Retry system is employed.
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