Canon LBP5000 Series, Руководство по обслуживанию

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Chapter 2
2-20
F-2-24
The ETB unit consists of the following: ETB, ETB feed roller, ETB slave roller, transfer roller, color displacement/density sensor.
The ETB is driven by the main motor through the ETB feed roller. The transfer roller and the ETB slave roller operate in keeping with the ETB.
While printing is under way, the print paper is moved between the ETB and the photosensitive drum, during which time it receives an image. The ETB is also used
in relation to color displacement correction and image stabilization, during which a color displacement/image density detection pattern is drawn on the belt for
reading by the color displacement/density sensor.
The following mechanism is controlled in relation to the ETB unit:
- ETB cleaning
2.4.5.2 ETB Cleaning
0010-6065
LBP5000 / LBP5100
In ETB cleaning, the residual toner on the ETB is returned from the belt to the photosensitive drum to prevent soiling of the back of print paper.
The cleaning mechanism is executed by the DC controller for the following:
- when a jam has occurred
- when calibration has been suspended
- when a specific number of prints have been made
- when color displacement correction has been executed
- when image stabilization has been executed
When ETB cleaning starts the DC controller applies a negative bias to the photosensitive drum and negative and positive biases to the 4 transfer rollers (colors),
causing a difference in potential between the drum and the belt and, thus, moving both negatively and positively charged toner particles from the ETB to the pho-
tosensitive drum at the same time.
While cleaning is under way, the developing cylinder remains still, thus preventing movement of toner from inside the toner case to the ETB.
M1
DC controller PCB
MAIN MOTOR DRIVE signal
Main motor
ETB feed roller
Transfer roller
ETB driven roller
Color misregistration/Density sensor unit
ETB belt
Direction of belt rotation