Fresa G024, Руководство по обслуживанию

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MECHANICAL OVERVIEW 31 March, 1999
1-4
(1) OPC belt
The OPC (organic photoconductor) belt is the central part of the machine. This is
where the laser beam writes an image of the original.
(2) Charge
A negative corona discharge in darkness negatively charges the OPC belt. The
grid ensures the even distribution of charge over the OPC belt.
(3) Exposure
The laser beam from the laser diode (LD) goes through the lens and the mirror and
reaches the OPC belt. The beam discharges the areas of the OPC belt that it
illuminates. Turning the laser beam on and off, and varying the intensity of the
beam, creates a latent image on the OPC belt.
(4) Development
The development section consists of four independent development units, one for
each color (Y, C, M, and K) and the structure necessary to support them. These
modules are known as DTMs (Development Toner Magazines).
This unit forms visual images by allowing toner to adhere to portions of the OPC
belt where negative potentials are lower than the development bias. In this
machine, monocomponent toner is used (there is no carrier).
In black single-color mode (1C), the image is developed in K only. In full color
mode (4C), the image is developed in Y, C, M, and K, in that order.
(5) Transfer
This printer uses a transfer belt. Four toner images, each a different color, are
super-imposed onto each other on the transfer belt. The combined image is then
transferred to the paper.
(6) Transfer belt cleaning
A cleaning brush applies lubricant to the transfer belt to improve cleaning. Then, a
blade scrapes off the remaining toner on the transfer belt.
(7) Paper separation
Paper separates from the transfer belt when the belt curves away from it. The roller
at the end of the transfer belt is 31 mm in diameter.
(8) Paper transfer (secondary transfer)
A charge applied to the transfer roller attracts the toner from the transfer belt onto
the paper.
(9) Belt transfer (primary transfer)
A charge applied to the bias roller attracts toner from the OPC belt onto the transfer
belt.
(10) ID sensor
The ID sensor detects the density of the ID sensor pattern on the transfer belt. The
ID sensor outputs determine the process control conditions.