Epson 4880 C Service Manual

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 121CLEANING MECHANISM DRIVE
Figure 2-8. Drive Transmission Path
Figure 2-9. Cleaning Mechanism Drive LayoutFigure 2-10. Cleaning Mechanism Drive Components
ASF/Pump Motor
Planetary Lever (Spur Gear, 15.2)Combination Gear, 15.2, 25.6
Spur Gear, 19.2
Combination Gear, 13.6, 28.8
Pump Unit
ASF/Pump MotorPlanetary Lever
(Spur Gear, 15.2)Spur Gear, 19.2Combination Gear, 
13.6, 28.8
Combination Gear, 
15.2, 25.6
Pump Unit
ASF/Pump MotorPlanetary Lever
(Spur Gear, 15.2)Spur Gear, 19.2
Combination Gear, 
15.2, 25.6
Combination Gear, 
13.6, 28.8
Pump Unit 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 122DRIVE TRANSMISSION TO PUMP 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 2-11. Switching Drive Transmission Path (1)
2. The ASF/Pump Motor rotates by the required step number in the clockwise 
direction as seen from the Motor Pinion Gear side.
3. When the ASF/Pump Motor rotates in the clockwise direction, the 
Planetary Lever inside the DE mechanism descends toward the 
Combination Gear, 15.2, 25.6, and the Planetary Levers Spur Gear, 15.2, 
engages with the Combination Gear, 15.2, 25.6.4. 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 end.
Figure 2-12. 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 Pump Unit by the path 
shown in Figure 2-8.DE Lock Lever
1
2
Planetary LeverCombination Gear, 15.2, 25.6
Fixing Location 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 123 †ASF/Pump Motor (Stepping motor)
When the transmission path is switched to the Pump Unit side by Carriage 
Unit movement and the DE Lock Lever, the ASF/Pump Motor can drive the 
ink maintenance system such as pump and wiper, etc.
Movements of the ASF/Pump Motor drive transmission to the Pump Unit side 
are shown below.
Note : Rotation of the motor in the clockwise direction as seen from the Motor Pinion 
Gear is considered clockwise.†Pump Unit
Ink is sucked from head nozzles by having the pump driven through the 
cap (closed). This performs normal ink absorption, initial ink charge, 
cleaning, etc. Waste ink from the pump is sent to the Maintenance Tank 
through 2 small pipes.
†Head Cleaner
A structure of offsetting rubber and felt is used. By wiping/rubbing, ink and 
dirt adhering to the head nozzle surface is brushed off.
†Cap Assembly
When not printing, the Print Head (should) rest on the Cap Assembly to 
ensure that the nozzles dont clog. Also, the Print Head is in the capped 
position during ink charging, cleaning, and so on.
†Flushing Box
This receives ink ejected during flushing (dummy printing). The flushed ink 
flows through the pipe to the Maintenance Tank.
†Maintenance Tank (Waste Ink Absorber)
This receives waste ink discharged from the Pump Unit and Flushing Box. 
Waste ink is accumulated in a sponge in the Maintenance Tank.†Pump Phase Sensor
A transmissive photosensor is used, which is installed inside the Pump 
Unit. This uses the interrupting plate in the Pump Unit to detect the rotation 
angle of the pump.
Figure 2-13. Pump Phase Sensor Table 2-5. ASF/Pump Motor Rotation Directions and Functions
ASF/Pump Motor Rotation 
Direction
Function
Clockwise• Pump suction
• Wiper set
Counterclockwise• Pump release
• Wiper reset
Pump Phase Sensor
Interrupting Plate 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 124 NOTE:The table below explains Ink System terminology.
Table 2-6. Explanation of Operation
Operation
Explanation
Initial Ink Charge • This is the operation where the head is filled with ink for the 
first time. When the first ink cartridge is inserted (after all 8 
colors have been inserted), the initial ink charge operation is 
performed automatically.
• The initial charge flag is set when the printer is shipped from 
the factory, then after this operation, the initial filling flag is 
reset. The initial charge flag is also set after the Input Rank is 
run.
Flushing • In order to prevent the viscosity of the ink inside the head 
nozzles from increasing, the ink inside the Flushing Box is 
flushed out.
• Flushing is done when paper is set, when printing from the 
standby state, during continuous printing, during paper Eject, 
during paper cutting, etc.
Wiping Operation The Carriage Unit is moved from right to left along the rubber side 
of the wiper (the right half of the Wiper Blade) incorporated in the 
Pump Unit so that the head surface is rubbed with the rubber of 
the wiper.
Purpose:
• Before ink suction, removes the ink and other substances 
adhering to the head surface.
• Ensures close contact of the cap.
Rubbing 
OperationThe Carriage Unit is moved from left to right along the felt side of 
the wiper (the left half of the Wiper Plate) incorporated in the 
Pump Unit so that the head surface is rubbed with the felt of the 
wiper. For easy removal of adhering substances, the nozzle 
surface is wetted before rubbing operation by suction of a small 
amount of ink.
Purpose:
• Removes ink and other substances adhering strongly to the 
head surface.
• Ensures close contact of the cap.
Capping In order to prevent the ink viscosity from increasing while the 
printhead nozzles are not used, a rubber cap is placed over the 
Print Head nozzles when entering a shutdown operation. 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 1252.2.4  Carriage (CR) MechanismThis printer has a unique carriage mechanism for stable and high precision 
movement/printing of the on-carriage head for the print area of A2 paper width.
The Carriage mechanism is formed of the following components.
†Carriage Unit
†Carriage Shaft (front and rear)
†CR Motor
†PG/PO Motor
†CR_HP Sensor
†CR Encoder Sensor
†Multi Sensor
†PG Phase Sensor
†Cutter Solenoid
†CR Lock
This section describes the following items.
†Carriage Unit movement components
†Platen Gap adjustment components
†Cutter Solenoid/CR Lock MechanismFigure 2-14. Carriage Mechanism Components
PG/PO Motor
Carriage Unit CR Lock Cutter SolenoidMulti Sensor PG Phase SensorCarriage Shafts
CR Encoder Sensor
CR Motor CR_HP Sensor 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 1262.2.4.1  Carriage Unit Movement ComponentsTwo Carriage Shafts, each covered with a linear plate, and eight rollers 
(bearings) form the structure supporting the carriage.
The main structural components of the carriage movement mechanism and the 
functions of these components are described below.CARRIAGE MECHANISM DRIVE
Figure 2-15. Drive Transmission PathFigure 2-16. Carriage Mechanism Drive Components
Do not remove the screws securing the Carriage Shafts. 
They are adjusted/assembled at the factory in 1/100mm 
increments.
Carriage UnitCR MotorTiming Belt
Timing Belt
CR Motor
Carriage Unit 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 127 †CR Motor (DC motor)
The Carriage Unit moves left/right by the CR Motor drive. The Encoder 
Sensor installed in the Carriage Unit reads (linear encoder system) the slits 
of the CR Scale, and this signal is compared to the logic control value by 
the Main Board control circuit to perform feedback speed control. The 
control maintains high printing speed.
Drive transmission from the CR Motor to the Carriage Unit uses a durable 
timing belt that is easy to maintain.
The sensors used in the carriage movement components are described below.
†CR_HP Sensor (Carriage home position)
This is a transmissive photosensor installed at the printer right side. 
Insertion of the flag (a protrusion) on the Carriage Unit is detected as the 
carriage movement origin (home position). Sensor outputs are OFF in the 
HP range and ON outside the HP range.
†CR Encoder Sensor (Linear encoder)
Installed on the back of the Carriage Unit, this is uses pulse output (2 
channels) corresponding to the slit position on the CR Scale for CR Motor 
servo control and PTS (Print Timing Signal) formation. The resolution is 1/
180 inch.†Multi Sensor
This is a reflective sensor installed at the Carriage Unit lower left side, and 
it has multiple functions. For details on the Multi Sensor, refer to 2.2.7 
Multi Sensor (p.145).
Figure 2-17. Carriage Mechanism Detection Components
CR_HP Sensor FlagCR Motor CR Scale CR Encoder Sensor
Multi Sensor 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 1282.2.4.2  Platen Gap Adjustment ComponentsThe Carriage Unit (= Print Head) installation position must always maintain a 
fixed distance from the paper surface in order to preserve printing precision.
The Carriage Unit is supported by 2 Carriage Shafts. The Carriage Unit moves 
up and down with the rotation of the Carriage Shafts because of the eccentric 
bushings attached to both ends of each Carriage Shaft. This movement 
changes the gap between the Print Head surface and the Platen surface.
Main platen gap adjustment mechanism components and their functions are 
explained in the following sections.PLATEN GAP MECHANISM DRIVE
Figure 2-18. Drive Transmission PathFigure 2-19. Platen Gap Mechanism Drive Layout
Figure 2-20. Platen Gap Mechanism Drive Components
Spur Gear, 16PG/PO Motor
Combination Gear, 56, 8.8Combination Gear, 40, 20Carriage Shaft (rear)
Spur Gear, 36
CR Shaft Pulley (rear)
Timing Belt
CR Shaft Pulley (front)Carriage Shaft (front)
Planetary Holder (Spur Gear, 20, Planetary)Planetary Holder (Spur Gear, 16, Planetary)
CR Shaft Pulley (front) Spur Gear, 36 CR Shaft Pulley (rear)
Carriage Shaft 
(front)
Timing Belt
Combination Gear, 40, 20
Combination Gear, 56, 8.8Carriage Shaft 
(rear)
PG/PO 
Motor
Planetary Holder
(Spur Gear, 16, 
Planetary)Planetary Holder
(Spur Gear, 20, 
Planetary)Spur Gear, 16
Carriage Shaft 
(front)Timing Belt Spur Gear, 36Carriage Shaft 
(rear)CR Shaft Pulley (rear)
CR Shaft Pulley (front)
Combination Gear, 40, 20
Combination Gear, 56, 8.8PG/PO Motor
Spur Gear, 16
Planetary Holder
(Spur Gear, 20, 
Planetary) Planetary Holder
(Spur Gear, 16, 
Planetary) 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 129DRIVE TRANSMISSION TO CARRIAGE SHAFT
1. The Planetary Lock Lever (along with the DE Lock Lever) are moved to the 
right end by moving the Carriage Unit to the right end of the Carriage Shaft.
Figure 2-21. Switching Drive Transmission Path (1)
2. The PG/PO Motor rotates by the required step number in the clockwise 
direction as seen from the Motor Pinion Gear side.
3. When the PG/PO Motor rotates in the clockwise direction, the Planetary 
Holder raises up in the direction of the Combination gear, 56, 8.8, and the 
Planetary Holder Spur gear, 16, engages with the Combination gear, 56, 
8.8.4. The planetary Lock Lever fixes the Planetary Holder in place when the 
Carriage Unit moves the required step number to the left from the Carriage 
Shaft right end.
Figure 2-22. Switching Drive Transmission Path (2)
5. When the drive transmission path is switched by Step 1 through Step 4, 
PG/PO Motor drive is transferred to the Carriage Shaft by the path shown 
in Figure 2-18.
DE Lock Lever
1
2
Fixing Location 
						

							EPSON Stylus Pro 4400/4450/4800/4880/4880CRevision COperating Principles Printer Mechanism Components 130 †PG/PO Motor (Stepping motor)
When the transmission path is switched to the platen gap adjustment side 
by the Carriage unit movement and DE Lock Lever, the PG/PO Motor can 
automatically shift (rotation movement of Carriage Shafts, both front and 
rear) the PG position up or down.
Movements of the PG/PO Motor drive transmission to the Platen Gap 
adjustment side are shown below.
Note : Rotation of the motor in the clockwise direction as seen from the Motor Pinion 
Gear is considered clockwise.The Adjustment Lock Bushing rotates with the rotation of the Carriage Shaft. 
When Carriage Shaft rotation stops, the PG Lock Lever locks the Adjustment 
Lock Bushing. Securing the Adjustment Lock Bushing suppresses rotation of 
the Carriage Shaft and prevents fluctuation in platen gap. 
The locking position has 4 levels to match PG.
Figure 2-23. PG Setting PositionsThe sensors used in the platen gap adjustment components are described 
below.
†PG Phase Sensor
This is a transmissive sensor installed on the left side of the printer that 
detects the PG position (height of head from paper surface) and machine 
home position (home) at the time of adjustment movements. A reflective 
sensor is used to detect the flag position of the shield plate attached to the 
right side of the front Carriage Shaft. With machine home position as the 
standard, 4 head positions can be obtained. Table 2-7. PG/PO Motor Rotation Directions and Functions
PG/PO Motor Rotation Direction
Function
Clockwise PG small side → PG large side
Counterclockwise PG large side → PG small sidePG Lock Lever
PG minimum side
PG large side
Adjustment Lock Bushing
Table 2-8. PG Setting
Position
Gap 
Width
Application
Pulse Count from Origin
(Converted to 2-2 Phase 
Excitation)
Macimum 2.6mm Platen gap for thick paper 244
Large 2.1mm Platen gap for paper which can be 
soiled if setting is for thin paper176
Medium 1.5mm Platen gap fot specified thin paper 
which has frictional force more 
than the other thin paper.96
Small 1.2mm Platen gap for thin paper 60
Minimum 0.7mm Platen gap for film 0