d-Color MF4003/MF3303
P THEORY OF OPERATION > 1. d-Color MF4003/MF3303
P-30
(5)Transfer belt cleaning
• The toner image on the surface of the transfer belt is transferred onto the paper. (2nd transfer)
• Part of the toner image is left on the surface of the transfer belt after the 2nd transfer. A cleaning blade is provided on the transfer belt. It
functions to remove the residual toner (waste toner).
[1] Transfer belt [2] Transfer belt driven roller
[3] Waste toner collecting screw [4] Cleaning blade
[5] Drive transmission gear []
(a)Cleaning blade
• The cleaning blade, of a fixed blade type, is pressed up against the surface of the transfer belt at all times. No cleaning blade retraction
mechanism is provided.
• The waste toner on the surface of the transfer belt is scraped off as the transfer belt is rotated.
(b)Waste toner conveying/collecting mechanism
• Drive for the toner collecting screw comes from the transfer belt driven roller. (The toner collecting screw rotates in time with rotation of
the transfer belt.)
• The rotation of the toner collecting screw conveys waste toner scraped off the surface of the transfer belt toward the front of the
machine.
• There is a caking-of-toner prevention blade installed. It prevents waste toner from caking at the toner collecting screw section.
• The waste toner is discharged through the toner collecting port into the waste toner bottle.
• The waste toner is disposed of when a waste toner bottle which is detected to be full of waste toner is replaced with a new one and the
used waste toner bottle is discarded.
(6)Toner discharge port shutter mechanism
• A shutter mechanism is provided to prevent waste toner from being spilled from the waste toner discharge port when the transfer belt unit
is removed and reinstalled.
• The shutter is fitted to the transfer belt unit. When the transfer belt unit is removed, the waste toner discharge port is automatically
closed.
[1] Shutter -
(7)Cleaning blade foreign matter removal control
• The transfer belt is rotated backward to a small extent and then rotated forward to remove foreign matter (dust, toner, etc.) wedged
between the transfer belt and the edge of the cleaning blade.
(a)Operation timing
• The backward rotation control is provided at the completion of every print job.