Epson C 2900 Manual

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3. Functions of Major Functional Components
Major functional components of the printer are described below with illustrations.
These components are classified into the following blocks based on the configuration of the printer.
• Paper tray
• Paper Feeder
• SSI & Regi Assy
• Transfer Belt & Fuser Unit
• ROS ASSY
• TONER CARTRIDGE & Dispenser
• Drum Cartridge
• Drive
• Electrical
• Duplex
• 250 Paper Tray (Option)
3.1...

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GUIDE SIDE LGUIDE SIDE ASSY R
HOLDER ASSY RETARD (Retard Roller) END GUIDE
PLATE ASSY  BOTTOM
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3.2 Paper Feeder
3.2.1 Major functions
- Tray No Paper Sensor (SENSOR PHOTO: PL3.2.13)
The Tray No Paper Sensor detects the presence/absence of print media in the paper tray based on 
the position of ACTUATOR NO PAPER. (No paper: Sensor beam is blocked)
- SOLENOID FEED MSI (PL3.1.11)
Transmits the drive from the DRIVE ASSY MAIN to FEED ROLLER. (Refer to 6.4 DRIVE ASSY 
SUB)
Tray No Paper Sensor
ACTUATOR NO PAPER
(No...

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Confidential - ROLL ASSY FEED (PL3.2.4)
When the SOLENOID FEED MSI operates, the ROLL ASSY FEED starts rotating and the ROLL 
ASSY FEED feeds the paper. (Refer to 6.4 DRIVE ASSY SUB)
ROLL ASSY  FEED
SOLENOID FEED MSI
ROLL ASSY  FEED
SOLENOID FEED MSIDRIVE ASSY  MAIN
DRIVE ASSY  PH
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3.3 SSI & Regi Assy
- SENSOR PHOTO (SSI No Paper Sensor: PL3.2.13)
The SSI No Paper Sensor detects the presence/absence of print media in the SSI tray by the 
change in the actuator position.
Upon detecting the sheet, the Regi Roll rotates for a predetermined duration to feed the sheet. The 
sheet is fixed between the Rolls so that it may not fall from the SSI.
The Rolls stop immediately when the Regi Sensor detects...

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Confidential - SENSOR PHOTO (Regi Sensor: PL3.2.13)
The Regi Sensor detects that the lead edge of the print medium has reached the registration sec-
tion. (No paper: Sensor beam is blocked)
When the print medium is fed from the SSI, the Regi Sensor measures the sheet length (size).
The duration for which the Regi Sensor is ON is converted into the paper length.
ACTUATOR REGI IN ACTUATOR REGI IN
PAPER Regi Sensor Regi Sensor
From...

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Confidential - CLUTCH ASSY DRV(PL3.1.1)
The CLUTCH ASSY DRV transmits the driving torque from the DRIVE ASSY MAIN to ROLL ASSY 
REGI(PL3.2.9) to feed the print medium to the fuser unit section from the paper tray, SSI, or Duplex 
section. (Refer to 6.1 DRIVE ASSY MAIN)
To place the toner image at an appropriate position on the print medium, the timing of feeding from 
the Regi Assy is adjusted by the duration for which the CLUTCH...

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Confidential 3.3.1 Control of paper size
The printer doesn’t have switches for detecting paper size, and only length of paper is detected by the 
Regi Sensor when feeding paper. If printing data and paper size don’t match, error is sent to the ESS.
3.3.2 Paper detection by the Regi Sensor
Since the paper path from the SSI to the Regi Sensor and that from the Paper Tray to the Regi Sensor 
are different, the Regi Sensor is provided...

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3.4 Transfer Belt & Fuser Unit
3.4.1 Major functions
- TRANSFER ASSY (PL6.1.7)
• Belt
Belt feeds the paper to the direction of FUSER UNIT
• SENSOR ADC
SENSOR ADC reads the toner patch on the BELT, and converts it to voltage value. Voltage value 
is used to control the density of toner. (Refer to 5.3.1 Potential Control)
- FUSER UNIT (PL6.1.1)
The FUSER UNIT fixes toner which was transferred onto the paper but not...

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Roll Assy  Exit
Transfer ASSY
BeltSENSOR ADC
Blade Assy FUSER UNIT
Heat Roll
Heater LampThermostat
Temp. Sensor
(Contacted type)Temp. Sensor
(Un-contacting type) Pressure BELT Rear view illustration
Exit Sensor
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