Canon LBP5000 Series, Service Manual

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Chapter 2
2-12
F-2-15
The rigidity of print paper is used to separate it from the drum. (curvature separation)
To prevent a toner splash in print images (in the form of dots, mostly occurring in a low temperature, low humidity environment), the machine is equipped with a
static eliminator. The static eliminator is used after transfer to decrease the charge on the back of print paper, and also to help make sure of the proper movement
of paper.
2.4.1.6 Fixing block
0010-6060
LBP5000 / LBP5100
In this block, the toner image is permanently fused with the fibers of print paper.
Upon transfer to print paper in the transfer block, the toner image remains on the paper because of static bonding. It would, therefore, be disrupted if touched (e.g.,
by a hand). In this block, the toner and the print paper are subjected to mechanical pressure and heat so that the toner will melt and fuse with the fibers of the paper.
Step 6: Fixing
F-2-16
In this step, an on-demand fixing method is used to permanently fix the toner image on the print paper.
The machine uses a ceramic heater, which has a high heating efficiency; specifically, it starts up fast, and does not require power while the machine is in a standby
state. Its wait time, moreover, is short, and is generally characterized by its high energy efficiency.
The machine applies a positive DC bias to the fixing pressure roller to increase the retention of negatively charged toner on print paper, thus conversely preventing
the adhesion of unwanted toner on the fixing film (offset).
2.4.1.7 Drum cleaning block
0010-6062
LBP5000 / LBP5100
In the transfer block, not all the toner on the surface of the photosensitive drum is moved to the print paper; in other words, there will always be residual toner
remaining after transfer.
In the drum cleaning block, the surface of the photosensitive drum is "cleaned" in preparation for the upcoming print job, ensuring that the next image will also be
reproduced as desired.
Step 7: Drum cleaning
F-2-17
In preparation for the next print job, the machine uses the cleaning blade to scrape off the residual toner from the drum surface by way of "cleaning" the surface.
The toner thus removed from the drum surface is collected inside the cleaner casing.
Paper
Photosensitive drum
ETB belt
Transfer roller
DC bias
Static charge eliminator
Fixing heater
Fixing film unit
Fixing pressure roller
Paper
Toner
DC bias
Waste toner container
Cleaning blade
Photosensitive
drum
Residual (waste) toner