Epson 4880 C Service Manual

EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 141TRANSMISSION OF DRIVE TO PAPER EJECT UNIT
1. The Planetary Lock Lever (along with the DE Lock Lever) is moved to the 
right end by moving the Carriage Unit to the right end of the Carriage Shaft.
Figure 2-41. Switching Drive Transmission Path (1)
2. The PG/PO Motor rotates by the required step number in the 
counterclockwise direction as seen from the Motor Pinion Gear side.
3. By rotation of the...

EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 142 †PG/PO Motor (Stepping motor)
When the transmission path is switched to the Paper Eject Unit side by the 
Carriage Unit movement and DE Lock Lever, counterclockwise rotation of 
the PG/PO Motor performs eject switching movement as shown below. 
(Clockwise rotation does not occur.)Note : Rotation of the motor in the clockwise direction as seen from the Motor Pinion 
Gear is considered clockwise....

EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 1432.2.6.2  Release MechanismRELEASE MECHANISM DRIVE
Figure 2-45. Drive Transmission PathFigure 2-46. Release Mechanism Drive Layout
Figure 2-47. Release Mechanism Drive Components 
PG/PO MotorSpur Gear, 16Planetary Holder
(Spur Gear, 20, 
Planetary
)
Planetary Holder
(Spur Gear, 16, 
Planetary
)
Combination Gear, 36, 8.8
Spur Gear, 20
Combination Gear, 13.6, 20.8Combination Gear, 11.2, 24Spur Gear,...

EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 144RELEASE MECHANISM MOVEMENT
When the drive transmission path of the PG/PO Motor is switched by carriage 
movement, the driving force of the PG/PO Motor is transmitted to the Gate 
Roller by the path shown in Figure 2-45. (Refer to 
 Transmission of Drive to 
Paper Eject Unit 
(p.141) for information on switching the drive transmission 
path.)
Movement for PG/PO Motor drive switched to the release...

EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 1452.2.7  Multi Sensor2.2.7.1  OverviewThis printer is equipped with a Multi Sensor that provides multiple sensor 
functions with a single sensor unit. The Multi Sensor is a photosensor with 1 
light emitter and 2 light receivers and is mounted on the Carriage Unit. Light 
emitted from the white light LED is projected onto the paper or special pattern 
printed on the paper, and reading of the reflected...

EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 1462.2.7.2  Operations/FunctionsSENSOR SENSITIVITY ADJUSTMENT
Before performing any function/adjustment, the sensor sensitivity level must be 
set for use as a standard.
Specifically, paper gets fed and the LED light emission quantity should be 
adjusted to 3V that refers to the difference of the sensor output voltages that 
have been received between over the paper and over the no paper position 
(over...

EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 147PAPER WIDTH DETECTION
When paper is fed, the paper and platen are scanned and the change points of 
the detected reflective light levels (paper present level  paper absent level) 
are confirmed as the paper edges. The diagrams below show scan/detection 
timing.
Figure 2-52. Paper Width Detection Timing
PAPER LEFT/RIGHT EDGE DETECTION DURING PRINTING
This is performed during borderless printing. For...

EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 148DOT MISSING DETECTION
A pattern for dot missing detection is printed and dot missing is detected by 
scanning the pattern. The pattern is printed by all the nozzles, with 1 nozzle 
printing 1 block, and a block for a abnormal nozzle will not print. If dot missing 
is detected, the printer will execute cleaning automatically.
Figure 2-54. Dot Missing Detection Pattern
AUTOMATIC UNI-D ADJUSTMENT
A...

EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 149AUTOMATIC BI-D ADJUSTMENT
A pattern for adjustment is printed, the pattern is scanned and acceptable 
values are calculated from the collected values, and then adjustment is 
automatically executed. Two types of patterns are printed during adjustment: a 
rough adjustment pattern for detecting the approximate correction position and 
a fine adjustment pattern for detecting the exact adjustment...

EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 150 †Fine Adjustment Pattern
This is a pattern for calculating the exact correction value. It uses all nozzles 
and 3 Bi-D patterns are printed after being shifted by 1/1440 step for each 
color. The location detected with the most raised A/D values and the 2 
locations detected with the most lowered A/D values are averaged, and the 
averaged values of the 3 patterns are calculated again, with the...