Epson C 2900 Manual

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Epson AcuLaser C2900NRevision B
Confidential 1.3.2 Exposure
The exposure process forms an invisible electrostatic latent image on the negatively charged drum sur-
face by scanning it with laser beams.
This process is performed in parallel for yellow, magenta, cyan and black colors.
- Laser beams are emitted from the laser diode in the ROS ASSY. The surface of each color drum is 
scanned from end to end in the axial direction by the rotating polygon mirror, the...

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Confidential - The laser beam is irradiated according to the printing data (image data) output from the printer con-
troller. The laser beam is output only when printing data is pixels (micro points composing charac-
ters or pictures). (The laser diode lights up for parts to be developed by toner, and not for parts that 
are not to be developed.)
The drum surface irradiated by the laser beam becomes a conductor, and the negative...

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Confidential 1.3.3 Development
In the development process, toner is electrically attached to the invisible electrostatic latent image on 
the drum surface to form visible toner image on the drum.
This process is performed in parallel for yellow, magenta, cyan and black color independently.
- The toner in the toner cartridge is agitated by the built-in Agitator and fed into the developer. The 
Auger is driven by the toner motor.The...

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Epson AcuLaser C2900NRevision B
Confidential
HVPSDrum
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: Negative electric charge
: Positive electric charge
: Toner
: Carrier
Trimmer Rod Paddle Toner Cartridge
Auger Auger
Magnet Roll
Agitator
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Epson AcuLaser C2900NRevision B
Confidential - Toner Dispense Mechanism
The toner in the toner cartridge goes through the following steps before reaching the developer.
Once the toner cartridge is set and the lever is moved toward the lock position, the JOINT ASSY 
DISP and the toner cartridge shutter move frontward, opening the toner supply port.
The toner supplied from the toner cartridge is carried toward the developer by the Auger in the 
HOUSING ASSY AUGER....

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Epson AcuLaser C2900NRevision B
Confidential 1.3.4 Transfer (Drum to Paper)
In the transfer process, toner image formed on the drum surface is transferred onto the surface of the 
paper. The toner is transferred onto the paper in the order of Y, M, C, and K.
-BTR
The BTR (Bias Transfer Roll) is a conductive roll, to which the positive voltage is applied from the 
High Voltage Power Supply (HVPS). The BTR contacts the rear side of the Belt and applies the...

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Epson AcuLaser C2900NRevision B
Confidential
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Confidential 1.3.5 Cleaning (DRUM)
In the Cleaning process, excess toner and charge is removed from the drum and BCR surfaces.
- Drum cleaning
The excess toner that was not transferred to the Transfer Belt remains on the drum surface. To 
prevent troubles in the subsequent processes, the excess toner is scraped off by the Cleaning 
Blade in contact with the drum, and then collected into the collection box as described in 1.3.8...

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Confidential 1.3.6 Fusing
In the fusing process, toner is fixed on the paper by heat and pressure.
- The toner particles are melted by the Heat Roll heated by the Heater lamp, and fused onto the print 
medium by the pressure between the Heat Roll and the Belt.
- The Belt friction-driven by the Heat Roll nips the print media against the Heat Roll using the pres-
surizing mechanism it contains.
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PaperSpring Nip
Felt
Belt...

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Confidential 1.3.7 Cleaning (Transfer ASSY)
In the Cleaning (Transfer ASSY) process, the transfer belt is cleaned by removing the excess toner 
on its surface (for the density measurement of ADC toner patch).
- Collecting excess toner from the transfer belt
(1) Toner on the BELT is scraped off by the Cleaner Blade that is in contact with the Drum.
(2) The removed toner is dropped into the Cleaner BOX.
Belt
Transfer ASSY 
Cleaner...