Konica Minolta bizhub C658 Service Manual page 1856

bizhub C658/C558/C458/C368/C308/C258
• When the tray 1/2 upper limit sensor is blocked, the tray 1/2 lift-up motor will stop to stop lift-up the paper lift-up plate.
• The sequence of these operations is repeated to keep constant the pressure between the pick-up roller and paper stack (paper take-
up pressure) regardless of the amount of paper still available for use.
11.3.2 Paper feed control (bizhub C368/C308/C258)
• Tray 1 and tray 2 are controlled in the same control procedure.
(1) Pick-up control
• The tray 1/2 paper feed clutch is energized after the lapse of a predetermined period of time after the print start signal.
• The driving force of the transport motor is transmitted to the pick-up roller and paper feed roller when the tray 1/2 paper feed clutch is
energized. These rollers rotate to pick up and feed a sheet of paper into the machine.
(2) Separation control
• The separation roller is pressed up against the feed roller by the pressure of a spring and an acting pressure generated from torque of
the torque limiter.
• The acting pressure of the feed roller/separation roller/torque limiter serves as the limit torque for preventing double feed.
• When there is no sheet of paper or only one sheet of paper between the separation roller and feed roller, the limit torque is exceeded and
the separation roller follows the rotation of the feed roller.
• If there are two or more sheets of paper between the separation roller and feed roller, the limit torque is greater than the friction force of
the paper, so that the separation roller is not rotated.
• The separation roller causes the lower sheet of paper in contact with the separator roller to be pushed backward in the direction of the
tray, so that the lower sheet of paper is properly separated.
• Only the upper paper contacting the feed roller is conveyed to the registration section.
[4]
[3]
[1] Feed roller
[3] Paper
(3) Periodical replacement parts
• The pick-up roller, feed roller, and separation roller are periodical replacement parts. These three rollers must be replaced with new ones
at the same time.
• None of the pick-up roller, feed roller, and separation roller is provided with a new article detection mechanism. When the three rollers
are replaced with new ones, the "1st." or "2nd." counter must be reset to zero using [Counter] -> [Life] of the Service Mode.
• The number of times tray 1/tray 2 has been subjected to paper feed operations can be checked with the "1st./2nd." counter of the Service
Mode.
Periodical replacement cycle
[1] Pick-up roller
• To improve exchangeability, the pick-up roller, feed roller, and separation roller are held in position on one side. At the time of
replacement, remove the paper feed tray and remove the C-clip on one side. It allows each of the three rollers to be removed.
O THEORY OF OPERATION bizhub C658/C558/C458/C368/C308/C258 > 11. PAPER
[1]
[2]
[1]
[2] Separation roller
[4] Pick-up roller
Paper feed operations 300,000 times
[2]
[2] Feed roller/Separation roller
O-81
FEED SECTION