Epson 4880 C Service Manual

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 1312.2.4.3  Cutter Solenoid/CR Lock MechanismInstalled on the front of the Carriage Unit, this is a DC solenoid for controlling 
cutter pressure of the cutter used for roll paper cutting.
In addition, the CR Lock Mechanism is used jointly so that when the Carriage 
Unit moves from the printing area further to the right of the capping position 
(CR_Home), the lock activates to prevent Carriage Unit movement. When the 
Cutter Solenoid turns ON with the Carriage Unit at capping position, the Cutter 
Solenoid attracts the Actuating Plate of the CR Lock releasing Kicker, the 
Kicker kicks the CR Lock, and then the CR Lock is released. The printer is also 
equipped with the mechanism to lock the Carriage Lock to prevent the Kicker 
from moving vertically during transportation to release the CR Lock.
NOTE:Refer to 1.2.7.4 Cut Specification (p.21).
Figure 2-24. Carriage Components: Cutter Solenoid
2.2.5  Paper Feed MechanismThis printer uses friction feed to carry out highly precise feeding of roll paper 
and cut sheets, and comprises a unique paper feed mechanism.
The paper feed mechanism is formed of the PF Motor, PF Roller, Sub Roller 
Unit, Driven Roller Unit and Paper Eject Roller.
Paper feed mechanism main components and their functions are described 
below.
Figure 2-25. Paper Feed Mechanism
Actuating Plate
Lock Lever for Transportation
Cutter Solenoid Kicker
CR Lock Cutter
PF Motor
Paper Eject Roller Driven Roller Unit
PF Roller
Sub Roller Unit 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 132PAPER FEED MECHANISM DRIVE
Figure 2-26. Drive Transmission Path
Figure 2-27. Paper Feed Mechanism Drive LayoutFigure 2-28. Paper Feed Mechanism Drive Components
PF Motor
PF Timing Belt
Speed-Reduction Pulley
Sub Roller Drive PF Pulley
Sub Roller Drive Belt
Paper Eject Roller BeltPaper Eject Roller Pulley
Paper Eject Roller
PF Roller
Sub Roller Unit
Sub Roller Drive Pulley
Sub Roller 
Drive BeltSub Roller 
Drive PF PulleySpeed-Reduction 
PulleyPF RollerPaper Eject Roller Belt
Paper Eject 
Roller
PF Timing Belt
PF Motor
Sub Roller Unit
Sub Roller 
Drive PulleyPaper Eject Roller Pulley
PF Timing 
Belt
PF MotorPaper Eject 
Roller PF Roller
Sub Roller Unit Sub Roller 
Drive Belt Sub Roller 
Drive Pulley
Paper Eject Roller Pulley
Sub Roller 
Drive PF PulleyPaper Eject 
Roller Belt Speed-Reduction 
Pulley 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 133 †PF Motor (DC motor)
With drive from the PF Motor, the grid of the loop scale installed above 
both PF Rollers is read by the Encoder Sensor, and feedback control is 
based on the output pulse. This control maintains high printing precision.
†Suction Fans
Suction Fans are mounted in the center inside the printer. This is designed 
to provide smooth paper feeding (prevents floating) by pulling the paper 
onto the platen surface by drawing air through multiple punched holes in 
the platen on the underside of the paper path and directing it toward the 
bottom of the printer body. Control of blowing force (rotation Duty control) 
for the fans is based on the printer operating condition (at paper set, during 
printing, etc.) and paper type.
Figure 2-29. Suction FansThe sensors used in the paper feed mechanism are described below.
†PF Encoder Sensor
Mounted at the left side of the printer, the sensors pulse output (2 
channels) corresponds to the slit position on the PF Scale and is used for 
servo control of the PF Motor and for formation of the PTS (Print Timing 
Signal). Resolution is 1/360 inch.
†PE Sensor
This reflective photosensor is mounted at the right side rear surface of the 
printer. This triggers the no paper condition when the paper trailing edge is 
detected and triggers paper setting start operations (start of suction fans, 
etc.) when the leading edge is detected during paper setting.
†Paper Lever/P_THICK Sensor (P_THICK, P_THICK_0.3)
This transmissive photosensor is mounted at the right side rear surface of 
the printer. Paper thickness is detected during paper setting by the change 
in movement of the paper thickness detection lever of the Driven Roller 
Unit.
Threshold values for paper thickness is set for 0.3~0.4mm (P_THICK0.3 
Sensor) and 0.8~0.9mm (P_THICK Sensor), and the sensor operates 
when the Paper Lever goes down.
Set detection values for the sensors are 0.3mm and 0.8mm, corresponding to 
the up/down position of the Paper Lever. Combined detection of both sensors 
detects the paper lever as up.
Suction Fans
Table 2-9. Modes
Paper Thickness
Shield Plate
Sensor Output
P_THICK_0.3
P_THICK
P_THICK_0.3
P_THICK
Less than 0.3mm No (open) No (open) L L
0.4mm or more
0.8mm or lessNo (open) Yes (closed) L H
0.9mm or more
1.8mm or lessYes (closed) Yes (closed) H H
Connector not 
connected––HH
Cancel increased 
pressure (Hi-Up)Yes (closed) No (open) H L 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 134 †Rear Manual Insertion Sensor
This reverse tension switch sensor (mechanical contact) is mounted at the 
rear surface of the printer. The sensor detects paper being fed from the 
manual insertion slot.
Figure 2-30. Paper Feed Mechanism Sensors
2.2.5.1  ASF Paper Feed MechanismThis printer is equipped with an ASF Unit for feeding cut sheet paper. 
Operating principles of the ASF Unit are described below.
Figure 2-31. ASF Paper Feed Mechanism
P_THICK_0.8 Sensor P_THICK_0.3 Sensor
Rear Manual Insertion Sensor 
PE Sensor PF Encoder Sensor
ASF Paper Sensor ASF Phase Sensor
Detector 
Wheel
ASF Unit LD RollerLD Roller 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 135ASF PAPER FEED MECHANISM DRIVE
Figure 2-32. Drive Transmission Path
Figure 2-33. ASF Paper Feed Mechanism Drive LayoutFigure 2-34. ASF Paper Feed Mechanism Drive Components
ASF/Pump Motor
Planetary Lever (Spur Gear, 15.2)
Combination Gear, 12, 22.4Combination Gear, 12.8, 36
Spur Gear, 33.6
ASF Unit (Spur Gear, 44.8)Combination Gear, 16.8, 24
Spur Gear, 25.6
Combination Gear, 16.8, 24ASF/Pump Motor Planetary Lever (Spur Gear, 15.2)
Combination Gear, 12, 22.4
Spur Gear, 25.6
Combination Gear, 
12.8, 36
Spur Gear, 33.6
ASF Unit 
(Spur Gear, 44.8)
Planetary Lever (Spur Gear, 15.2)
ASF/Pump Motor
Combination Gear, 
16.8, 24 Combination Gear, 12, 22.4
Spur Gear, 25.6
Combination Gear, 12.8, 36
Spur Gear, 33.6
ASF Unit 
(Spur Gear, 44.8) 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 136TRANSMISSION OF DRIVE TO ASF UNIT
1. The DE Lock Lever is moved to the right end by moving the Carriage Unit 
to the right end of the Carriage Shaft.
Figure 2-35. Switching Drive Transmission Path (1)
2. The ASF/Pump Motor rotates by the required step number in the 
counterclockwise direction as seen from the Motor Pinion Gear side.
3. By rotation of the ASF/Pump Motor in the counterclockwise direction, the 
Planetary Lever inside the DE mechanism raises in the direction of the 
Combination Gear, 12, 22.4, and the Spur Gear, 15.2, of the Planetary 
Lever engages with the Combination Gear, 12, 22.4.4. The DE Lock Lever fixes the Planetary Lever in place when the Carriage 
Unit moves the required step number to the left from the Carriage Shaft 
right.
Figure 2-36. Switching Drive Transmission Path (2)
5. When the drive transmission path is switched by Step 1 through Step 4, 
drive power of ASF/Pump Motor is transferred to the ASF Unit by the path 
shown in Figure 2-32.
DE Lock Lever
1
2
Fixing Location 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 137 †ASF/Pump Motor (Stepping motor)
When the transmission path is switched to the ASF Unit side by the 
Carriage Unit movement and DE Lock Lever, the ASF/Pump Motor can 
drive the LD Roller.
Movements of the ASF/Pump Motor drive transmission to the ASF Unit side 
are shown below.
Note : Rotation of the motor in the clockwise direction as seen from the Motor Pinion 
Gear is considered clockwise.The sensors used in the ASF paper feed mechanism are described below.
†ASF Paper Sensor
This reverse tension switch sensor (mechanical contact) is mounted at the 
center lower side of the printer. The sensor detects paper being fed from 
the ASF Unit.†ASF Phase Sensor
This transmissive photosensor is mounted at the right lower side of the 
printer. The Detector Wheel at the left side of the LD Roller and LD Roller 
Shaft is rotated by paper feed movement from the ASF Unit. There is a 
notch on the Detector Wheel, and the LD Roller position is detected by this 
sensor and the Detector Wheel notch.
Figure 2-37. ASF Phase Sensor Table 2-10. ASF/Pump Motor Rotation Directions and Functions
ASF/Pump Motor Rotation Direction
Function
Clockwise LD Roller Reverse Rotation
Counterclockwise LD Roller Normal Rotation
Table 2-11. LD Roller and Detector WheelLD Roller Position
Detector Wheel Notch
Outside home position No (closed)
Home Position Yes (open)
ASF Phase Sensor
Detector Wheel
Notch 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 138LIFTER MOVEMENT (RAISING THE HOPPER)
1. When a print command is received from the PC, the LD Roller which has 
been in standby condition first rotates to the paper feed side 
(counterclockwise) by the required step number and then rotates in the 
opposite direction from the paper feed side (clockwise) by the required 
step number to return any paper remaining between the LD Roller and the 
Separation Pad to the tray.
2. After completion of the paper return movement, the Release Hopper Lever 
rotates counterclockwise with the LD Roller. When the Edge Guide Fixing 
Lever releases the hook being pressed by the Release Hopper Lever, the 
tension of the Compression Spring is released and raises the Hopper.3. The LD Roller rotates in the counterclockwise direction and picks up paper.
„Skew Correction Mode 1
1. Feeds the paper leading edge by 3.5mm between the Sub Roller 
and Gate Roller.
2. The LD Roller stops, and reverse rotation of the Gate Roller and 
Sub Roller corrects the skew by pushing back the paper being fed.
FlagLD Roller
Phase Detection 
Position
Paper
Standby Position
HopperRelease 
Hopper Lever
Compression 
Spring
Edge Guide Fixing Lever
3.5mm
Gate RollerSub Roller
Stops 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 139 „Skew Correction Mode 2
1. The paper hits against the Gate Roller and Sub Roller. The Gate 
Roller and Sub Roller are stopped at this time.
2. Skew is corrected by the LD Roller pushing forward the unfed 
paper.
4. After feeding the paper, the LD Roller rotates in the counterclockwise 
direction and returns to the standby position.
5. The LD Roller in standby position then rotates in the clockwise direction by 
the required step number to return paper remaining between the LD Roller 
and Separation Pad to the tray. Then the roller returns to the standby 
position again.
Stops
Contact Location 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 1402.2.6  Paper Eject/Release MechanismThis printer has a paper eject mechanism that switches eject according to the 
paper feed device and media used and has a release mechanism that applies 
pressure/release by the driven roller.
Operating principles of the eject mechanism and release mechanism are 
described below.2.2.6.1  Paper Eject MechanismPAPER MECHANISM DRIVE
Figure 2-38. Drive Transmission PathFigure 2-39. Paper Eject Mechanism Drive Layout
Figure 2-40. Paper Eject Mechanism Drive Components
PG/PO MotorSpur Gear, 16Planetary Holder 
(Spur Gear, 20, 
Planetary
)
Paper Eject Unit
(Paper Eject Frame Holder 
(right))
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, 21.6, Release
Spur Gear, 33.6, B
Combination Gear, 19.2, 33.6
Spur Gear, 20Spur Gear, 28
Eject Planetary Unit
(Spur Gear, 17.6, 
planetary
)
Spur Gear, 32.8
Eject Switch Lever, R
(Spur Gear, 44.8, Eject)
Transmission Frame Shaft
(Spur Gear, 16, Frame, 
Transmission)
Switching Rib
(Spur Gear, 15.2)
Combination Gear, 24, 36
Eject Switch Lever, R
(Spur Gear, 44.8, Eject)Switching Rib
(Spur Gear, 15.2)Planetary Holder 
(Spur Gear, 20, 
Planetary
)
Planetary Holder 
(Spur Gear, 16, 
Planetary
)
Spur Gear, 20Spur Gear, 16
PG/PO Motor
Combination 
Gear, 13.6, 20.8
Combination 
Gear, 11.2, 24
Spur Gear, 21.6, 
Release Paper Eject Unit
(Paper Eject Frame 
Holder (right))
Spur gear, 32.8
Eject Planetary Unit
(Spur Gear, 17.6, Planetary)
Spur Gear, 28
Combination 
Gear, 19.2, 33.6
Spur Gear, 33.6, B
Combination 
Gear, 36, 8.8Spur Gear, 20
Combination 
Gear, 24, 36Transmission Frame 
Shaft (Spur Gear, 16, 
Frame, Transmission)
Switching Rib
(Spur Gear, 15.2)Spur Gear, 20
Spur Gear, 28Spur Gear, 33.6, B
Combination Gear, 24, 36
Planetary Holder 
(Spur Gear, 20, 
Planetary
)
Spur Gear, 16PG/PO 
Motor
Paper Eject Unit
(Paper Eject Frame 
Holder (right))
Eject Switch Lever, R
(Spur Gear, 44.8, Eject)
Spur gear, 32.8
Eject Planetary Unit
(Spur Gear, 17.6, Planetary)
Combination 
Gear, 19.2, 33.6Transmission Frame 
Shaft (Spur Gear, 16, 
Frame, Transmission)
Planetary Holder 
(Spur Gear, 16, 
Planetary
)Combination 
Gear, 36, 8.8Spur Gear, 21.6, 
ReleaseCombination
Gear, 13.6, 
20.8
Spur Gear, 
20
Combination
Gear, 11.2, 
24