Konica Minolta bizhub C658 Service Manual page 1904

bizhub C658/C558/C458/C368/C308/C258
[11] 2nd transfer roller
[13] Paper exit roller
(1) Transport roller control
• The ADU transport motor drives the ADU transport roller1 and ADU transport roller2.
• The ADU transport roller3 and ADU transport roller4 are driven by controlling rotation of the transport motor with the ADU transport
clutch. (bizhub C368/C308/C258)
• The ADU transport motor2 drives the ADU transport roller3 and ADU transport roller4. (bizhub C658/C558/C458)
(2) Paper entrance control (bizhub C368/C308/C258)
• The switchback motor at the paper exit/reverse section is deenergized to stop transport of the paper temporarily. (stop position 1) The
switchback motor thereafter rotates in reverse to transport the paper into the duplex section.
• At the same time of backward rotation of the switchback motor, the ADU transport motor is energized and the ADU transport roller1 and
ADU transport roller2 start rotating.
• The ADU paper passage sensor1 located downstream of the ADU transport roller1 detects the leading edge of the paper transported to
the duplex section.
• If a preceding sheet of paper being transported through the duplex section is yet to reach a predetermined position downstream of the
registration roller, the ADU transport motor is deenergized to stop transport of the paper temporarily. (stop position 2)
• When the advanced sheet of paper moves past the specified position, ADU transport motor1 is energized to resume the transport of
paper.
• If the ADU paper passage sensor2 does not detect the leading edge of the paper even after the lapse of a predetermined period of time
after the ADU paper passage sensor1 has detected the leading edge of the paper, the machine determines that a paper misfeed occurs
at the duplex transport part.
• When the leading edge of the paper reaches the specified position, ADU transport clutch is energized and ADU transport roller 3 and
ADU transport roller 4 transports paper.
• ADU paper passage sensor2 detects the leading edge of the paper.
• When the paper moves past ADU transport roller 4 and reaches the specified position, ADU transport clutch is deenergized to stop the
transport of the paper temporarily (stop position 3).
(3) Paper entrance control (bizhub C658/C558/C458)
• The switchback motor at the paper exit section is deenergized to stop transport of the paper temporarily (stop position 1). The switchback
motor thereafter rotates in reverse to transport the paper into the duplex section.
• When the switchback motor starts reverse rotation, ADU transport motor1 is energized and ADU transport roller 1 and ADU transport
roller 2 transports the paper.
• The ADU paper passage sensor1 located downstream of the ADU transport roller1 detects the leading edge of the paper transported to
the duplex section.
• If a preceding sheet of paper being transported through the duplex section is yet to reach a predetermined position downstream of the
registration roller, the ADU transport motor1 is deenergized to stop transport of the paper temporarily. (stop position 2)
• When the advanced sheet of paper moves past the specified position, ADU transport motor1 is energized to resume the transport of
paper.
• If ADU paper passage sensor2 is unable to detect the leading edge of the paper even after the lapse of a predetermined period of time
after ADU paper passage sensor1 has detected the leading edge of the paper, the machine determines that a paper misfeed occurs at
the duplex transport part.
• When the leading edge of the paper reaches the specified position, ADU transport motor2 is energized and ADU transport roller 3 and
ADU transport roller 4 transports paper.
• ADU paper passage sensor2 detects the leading edge of the paper.
• When the paper moves past ADU transport roller 4 and reaches the specified position, ADU transport motor2 is deenergized to stop the
transport of the paper temporarily (stop position 3).
(4) Duplex paper feed control
• At predetermined paper feed timing, the ADU transport clutch is energized to resume the transport of the paper. ADU transport motor1 is
also energized if it has been deenergized. (bizhub C368/C308/C258)
• At predetermined paper feed timing, the ADU transport motor2 is energized to resume the transport of the paper. ADU transport motor1
is also energized if it has been deenergized. (bizhub C658/C558/C458)
• The paper is fed from ADU transport roller 4 onto the registration roller at the vertical transport part.
16.5.2 Duplex circulation control
• The duplex circulation control is performed differently according to the length of the paper path direction.
Length of paper in the feed direction
458 mm or less
432 mm or less
216 mm or less
(1) One-sheet circulation operation
• After the second side is printed for each sheet, the paper is transported to the duplex pre-registration section. After the first side is
printed, the paper is then discharged outside of the machine.
O THEORY OF OPERATION bizhub C658/C558/C458/C368/C308/C258 > 16.
[12] Fusing unit
[14] Reverse roller
Duplex circulation control
One-sheet circulation operation
Two-sheet circulation operation
Three-sheet circulation operation
O-129
DUPLEX SECTION