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EPSON Stylus COLOR 800 Service Manual 2-i

Chapter 2Operating Principles

2.1 Overview............. .............. .............. ............... .............. .............. .............. .............. ............ 2-12.2 Printer Mechanism Operating Principles .................................. ....................................... ....2-1

2.2.1 Printing Mechanism .................. ..................... ..................... ..................... .......... 2-22.2.1.1 Printing Process .................. ..................... ..................... .................... 2-32.2.1.2 Printing Methods ..................... ..................... ..................... ................ 2-3

2.2.2 Carriage (CR) Mechanism..................................................................................2-42.2.3 Paper Feed Mechanism .............. .............. .............. .............. .............. ............... 2-62.2.4 Platen Gap (PG) Adjust Mechanism...................................................................2-72.2.5 CR Lock Mechanism............... .............. .............. .............. .............. .............. ..... 2-82.2.6 ASF Mechanism.................................................................................................2-82.2.7 Ink System...... ................. ................. ................ ................. ................. ............. 2-11

2.2.7.1 Pump Mechanism.............. .................... ..................... ..................... 2-122.2.7.2 Capping Mechanism........................ ........................... ..................... 2-14

2.3 Circuit Operating Principles ..................... .................... ..................... ..................... ........... 2-15

2.3.1 C202 PSB/PSE Board.......... .............. ............... .............. .............. .............. ..... 2-152.3.2 C202 MAIN Control Board........ ............... .............. .............. .............. .............. . 2-18

2.3.2.1 Printhead Driver Circuit ........................ ........................... ................ 2-202.3.2.2 Reset Circuits ..................... ..................... ..................... ................... 2-222.3.2.3 Motor Driver Circuits.... ..................... ..................... ..................... ..... 2-242.3.2.4 Sensor Circuits .................... ..................... ..................... .................. 2-25

2.4 Ink System Management .............. .............. .............. .............. .............. ............... ............. 2-262.4.1 Ink System Operations.. ..................... ..................... ..................... .................... 2-262.4.2 Timers and Counters............. ..................... .................... ..................... ............. 2-272.4.3 Ink System Sequences....................... ............... .............. .............. .............. ..... 2-28

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Principles of Operation

EPSON Stylus COLOR 800 Service Manual 2-1

2.1 Overview

This chapter provides information on the printer mechanism, electrical circuits, and ink system. Theoperating principles for each device in the printer mechanism are described individually. The description ofcircuits covers the C202 PSB/PSE board and C202 MAIN board.

2.2 Printer Mechanism Operating Principles

This printer is composed mainly of the printing mechanism, paper feed mechanism, carriage mechanism,pump mechanism, and ASF mechanism. There are three motors: the carriage motor (CR motor), paper feedmotor, (PF motor) and pump motor. Table 2-1 shows each motor and corresponding units driven.

Motor Unit Driven

PF motor PF roller assembly, CR lock lever

CR motor CR unit, capping unit

Pump motor Pump unit, capping unit, wiper, ASF unit

When the PF motor rotates clockwise, its torque drives the PF roller assembly and releases the CR locklever. When the PF motor rotates counterclockwise, the torque locks the CR lock lever. The CR motortransmits torque via the timing belt to move the carriage in both right and left directions in parallel with theplaten. The torque from the pump motor, switched by the disengage mechanism, is transmitted to the ASFand the pump. The figure below shows the block structure of the printer mechanism.

Table 2-1. Motor and the Assembly it Drives

Carriage MechanismPrint Mechanism

CR MotorSlider Mechanism Black Color

Pump Motor

PF Motor

Pump Mechanism

Disengage Mechanism

ASF Mechanism

CR Lock Mechanism

Paper Feed Mechanism

Figure 2-1. Printer Mechanism Block Diagram

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2-2 EPSON Stylus COLOR 800 Service Manual

2.2.1 Printing Mechanism

The printer uses an on-demand ink jet system to print, just as with other EPSON ink jet printers. This printer,however, has a newly designed MACH head, which ensures high printing quality at a higher speed. Theprinter is equipped with separate printheads of the same type: one for black and one for each of the threecolors (magenta, cyan, and yellow). The quick penetration-type of black and color ink is also improved forthis printer, which enables users to print images at a high quality on normal paper.

Printhead

The black and color printheads for this printer use the newly designed MACH head (E-CHIPS head). Theprinthead structure is the same as for the previous CHIPS head, except for the nozzle configuration. Theblack head for this printer has 128 nozzles (32 nozzles in each of 4 rows), which is as twice as many asprevious EPSON ink jet printers. The color head has 192 nozzles (32 nozzles for each of 6 rows), whichis 3 times as many as previous EPSON ink jet printers. Therefore, print quality as well as speed for thisprinter is higher than ever. Nozzle structure for this printhead is shown in the figure below.

PZT

PZT is an abbreviation for piezo electric element. The print signal from the C202 MAIN board is sentthrough the driver board on the printhead unit and to the PZT. Then, the PZT pushes the top of thecavity, which contains stored ink, and discharges the ink from each nozzle on the nozzle plate.

Cavity Set

Ink absorbed from the ink cartridge goes through the filter and is stored temporarily in this tank(called a cavity), which is driven by the PZT.

Nozzle Plate

The board with nozzle holes on the printhead surface is called the nozzle plate.

Printhead Driver Board

Ink Cartridge Sensor Lever

Cartridge Needle

Filter

Ink TubeCavity

PZT

Nozzle Plate

(Ink Cartridge)

Figure 2-2. Printhead Structure

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Filter

When the ink cartridge is installed, if any dirt or dust around the cartridge needles is absorbed intothe head internally, there is a great possibility of nozzles clogging and disturbance of ink flow, whichwill finally cause alignment failure and missing dots. To prevent this, a fi lter is installed below thecartridge needle, and ink is once fil tered here.

2.2.1.1 Printing Process

The stages below describe how the on-demand ink jet system ejects the ink from each printhead nozzle.

Stage 1 Normal stateWhen no print signal is output, the PZT does not move and is in the waiting state (normal state).

Stage 2 Ejecting stateWhen a print signal is output from the C202 MAIN board, the nozzle selector IC mounted on the head driverboard latches data in 1-byte units. The appropriate PZT latched by nozzle selector is pushed into the cavityby applying a common voltage from the C202 MAIN board. By this operation, ink stored in the cavity spurtsout from the nozzle.

During ink charging or cleaning, ink left in the cavity is vacuumed out by the pump mechanism via thecapping unit. Then it is ejected to the waste ink drain tank. The cavity is refilled with ink from the inkcartridge during printing or other operations. Ink viscosity tends to change with the temperature around theheads, and this change in viscosity could result in low printing quality. This, however, is avoided by attachinga thermistor directly to the driver circuit board. It is used to determine the proper drive pulse automaticallybased on the detected temperature.

2.2.1.2 Printing Methods

This printer uses three kinds of dot to compose the print image: the normal dot, the double-firing normal dot,and the micro dot. Each dot is selected to control printing depending on conditions, such as the paper typeand the print resolution set through the printer driver.

Normal Dot / Double-Firing Normal Dot Print Modes

Normal dot/double-firing normal dot print modes are available for both black and color printing. Thenormal dot print mode forms single dot with two head drive pulses. In this mode, the dot diameter isexpanded to solve the white banding problem that occurs in solid printing at 360 dpi. This printer is,however, designed to use less ink than other printers to print at 1440 dpi, the maximum resolution on ahorizontal line. Therefore, the double-firing normal dot and normal dot modes used in this printer areconsidered equivalent, respectively, to the normal dot and micro dot modes used in previous ink jetprinters. Double-firing normal dot mode is usually selected for printing 360 dpi, and the normal dot modeis used for printing in 720 x 360 dpi or 720 dpi x 720 dpi, depending on the paper type.

Nozzle Cavity

Piezo

Normal State Ejecting State

Ejected ink

Figure 2-3. Print Process

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EPSON Micro Dot Printing

Both black and color printing can be performed in micro dot print mode. In normal dot printing, one dot isformed by two pulses. On the other hand, EPSON micro dot printing forms one dot with a single pulse,using less ink. As mentioned above, micro dot printing for this printer is controlled to use less ink tocreate 1440 dpi images, the maximum resolution in a horizontal line. This mode is used for printing in

720 or 1440 dpi by controlling the ink firing duty.Microweave Printing

This function enhances graphic image quality by eliminating white banding on each line. The printer isequipped with a new Microweave print mode and controlled to form a horizontal line using two types ofnozzle. In this mode, the printer can prevent color inks from mixing with each other before drying andcan provide clearer colors in output. Microweave printing can be selected through the printer driver.

2.2.2 Carriage (CR) Mechanism

The CR mechanism is composed of the CR motor, timing belt, CR guide shaft, top frame, and homeposition (HP) sensor. Torque from the CR motor is transmitted to the CR unit via the timing belt to move theCR unit right and left along the CR guide shaft, depending on the direction the CR motor rotates. When the

CR unit returns to HP position, it is detected by the HP sensor mounted on the right end of the top frame,and the information is fed back to gate array IC2 (E05B33CB). Figure 2-4 illustrates the CR mechanism.

The CR motor, which drives the CR mechanism, is a 4-phase/200-pole/HB-type stepping motor controlledby a constant-current bipolar control system. The current control signal for each phase and the phase controlsignal output from gate array IC2 E05B33CB are converted into CR motor control signals by IC13 bipolardriver UDN2917EB to control the CR motor. See Table 2-2 and Table 2-3, which show CR specifications anddrive frequencies.

Timing Belt

Driven Pulley CR Guide Shaft

HP Sensor

CR Motor

CR Motor Pinion GearCR Unit

Figure 2-4. Carriage Mechanism

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Item Description

Motor type 4-phase / 200-pole / HB-type stepping motor

Drive voltage 42 VDC 5%

Coil resistance 7.8 10% at 77 F (25 C) per phaseInductance 14 mH 20% (1 KHz, 1 V rms)

Drive frequency 240 ~ 4080 Hz

Excitation mode Bipolar drive

Minimum step 1/120 inch / pulse (2-2 phase drive), 1/240 inch / pulse (1-2 phase drive)1-480 inch / pulse (W1-2 phase drive)

Modes CR Speed(CPS)

DriveFrequency

Drive System and Acceleration/Deceleration Steps

Acceleration/Deceleration

(Hz) A*2: 1, D*

3: 2 A: 2, D: 2 Constant Pulses*

1

Fast skip 340 4080 64 (W1-2) 164 (2-2) (2-2) 180

Draft 266.7 3200 88 (W1-2) 86 (2-2) (2-2) 108

LQ 200 2400 432 (W1-2) (W1-2) 108

Text LQ 200 2400 240 (W1-2) (W1-2) 60

SLQ 100 1200 432 (W1-2) (W1-2) 108

Capping 90 1080 64 (W1-2) (W1-2) 16

Wiping 2 80 960 64 (W1-2) (W1-2) 16

Wiping 40 480 16 (W1-2) (W1-2) 4

Capping(open)

20 240 8 (W1-2) (W1-2) 2

Constantvalue

20 240 (W1-2)

Note: *1: Steps: reduced to 2-2 phase

*2: Acceleration*3: Deceleration

Table 2-2. CR Motor Specifications

Table 2-3. CR Motor Driver Terms

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2.2.3 Paper Feed Mechanism

To improve feeding speed, this printer is equipped with a PF motor that is used only to feed paper. The drivefrom the pump motor is used to load paper from the ASF and the drive from the PF roller is independentlyused only to feed paper. The paper feed mechanism is separated into two parts: the paper feed part,including the PF roller in the main assembly; and the paper eject part, including the paper eject roller in themain assembly. The PF roller is coated with a powdery material to improve paper feed accuracy. The PFmotor in the rear left part of the printer mechanism transmits torque via the combination gear (14 mm, 31.5mm) and gear (70 mm) to the PF roller assembly to feed loaded paper. The torque is then transmitted fromthe gear (17 mm) on the paper feed roller assembly to the paper eject roller via the gear (19 mm) to ejectpaper. Torque is transmitted in the following order:

Paper feed part

1. PF motor pinion gear 2. Combination gear (14 mm, 31.5 mm) 3. Gear (70 mm) 4. PF roller assembly

Paper eject part

1. PF motor pinion gear 2. Combination gear (14 mm, 31.5 mm) 3. Gear (70 mm)

4. Gear (17 mm), PF roller assembly 5. Gear (19 mm), front paper guide assembly

6. Paper eject roller assembly, front paper eject assembly

This printer uses a 4-phase/96-pole/HB-type pulse motor controlled by a bipolar constant-voltage system asthe PF motor. The current control signal for each phase and phase control signal output from gate array IC2E05B33CB are converted into PF motor control signals by the IC16 bipolar driver UDN2917EB to control thePF motor. Since the power switch for this printer is wired in the secondary circuit, voltage remains constant

until the loaded paper is ejected after printer power is turned off. Table 2-4 and Table 2-5 show PF motorspecifications and PF motor drive frequencies, respectively.

PF Motor Pinion Gear

PF Motor

Combination Gear(14 mm, 31.5 mm)

PF Roller Assembly

Timing Belt

HP SensorCR Motor

CR UnitFront PaperGuide Assembly

Paper EjectRollerGear

(17 mm)Gear

(19 mm)

Gear(70 mm)

Figure 2-5. Paper Feed Mechanism

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Item Description

Motor type 4-phase / 96-pole / HB-type pulse motor

Drive voltage 42 VDC 5% (The voltage applied to the driver)

Coil resistance 7.8 10%, at 77 F (25 C) per phaseInductance 14 mH 20% (1 KHz, 1 V rms)



Minimum step 1/120 inch / pulse (2-2 phase drive)

ModeFeedingSpeed

DriveFrequency

PulseIntervals

Acceleration Stepsfor Each Phase

Deceleration Stepsfor Each Phase

(inch/sec) (Hz) (s) W1-2 2-2 1-2 W1-2 2-2 1-2

Normal feed 5 3600 278 50 50

Fast feed 6 4320 231 60 60

Slow feed 2.5 1800 556 20 20 At loading 3 22160 463 30 30

Micro adjust 1 1.25 900 1111 2 2

Micro adjust 2 0.55 400 2500

Note: Drive frequency and pulse intervals are reduced to 2-2 phase.

2.2.4 Platen Gap (PG) Adjust Mechanism

The PG adjust mechanism, at the left of the printer mechanism, consists of the PG lever, PF sub lever,right/left parallelism adjustment bushings, and CR guide shaft. The PG adjust mechanism is designed tokeep the platen gap correct for the paper thickness to prevent ink from smearing. The PG lever joins the CRguide shaft, which has an eccentricity via PG sub lever. Switching the lever from 0 to + rotates the CR

shaft and changes the platen gap from narrow to wide. Figure 2-6 shows the PG adjust mechanism.

Table 2-4. PF Motor Specifications

Table 2-5. PF Motor Drive Terms

PG Lever Position +

PG Lever Position 0

PG Lever

PG Sub Lever CR Guide Shaft

Figure 2-6. PG Adjust Mechanism

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2.2.5 CR Lock Mechanism

The CR lock lever, on the right side of the printer mechanism, is composed of the PF motor, PF rollerassembly, CR lock lever (stopper lever), and so on. When no paper is loaded and no data stored, the CRlock mechanism fixes the CR unit in the capping position. This is done by rotating the PF motor clockwise inthe specified steps to move the lock lever at the right end of the PF roller to the left of the CR unit. The locklever is released from the lock position when the PF motor rotates counterclockwise in the specified steps.The PF motor drive is transmitted in the following order:

1. PF motor pinion gear 2. Combination gear (14 mm, 31.5 mm) 3. Gear (70 mm)

4. PF roller assembly 5. Lock lever

The figure below shows the CR lock mechanism.

2.2.6 ASF Mechanism

The ASF mechanism, which consists of the pump motor, slider mechanism, disengage mechanism, andASF unit, loads paper into the paper feed mechanism. When the CR unit returns to the home position, itpushes the slider in the slider mechanism to the right, and the gear (16 mm) in the slider mechanism thenengages the change cam in the disengage mechanism. With this motion, the pump motor rotates in thespecified steps counterclockwise, which switches the change cam to the ASF unit side. Then torque fromthe pump motor is transmitted to the ASF unit. The process in which drive from the pump unit is switched tothe ASF unit side is described below. Figure 2-8 illustrates the process for the switching operation.

Disengage Mechanism Switch Process1. CR moves to home position.2. Slider moves to the right end (slider mechanism).3. The gear (16 mm) engages the change cam in the disengage mechanism (slider mechanism).4. The change cam switches to the ASF side (disengage mechanism).5. The combination gear (14.4 mm, 21.6 mm) moves to the left.

PF Motor Pinion Gear

PF Motor

Combination Gear(14 mm, 31.5 mm)

PF Roller Assembly

Timing Belt

HP Sensor

CR Motor

Lock Lever

Gear(17 mm)

Gear(19 mm)

Gear(70 mm)

Paper EjectRoller

FrontPaper Guide

Compression Spring(5.85 g)

Figure 2-7. CR Lock Mechanism

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The figure below shows movements in steps 3 to 5.

Transmission Process for Pump Motor Torque

1. Pump motor pinion gear 2. Combination gear (12 mm, 26 mm)

3. Combination gear (14.4 mm, 21.6 mm) 4. Gear (16.8 mm)

5. Combination gear (12 mm, 20.8 mm) 6. Gear (27.2 mm), ASF unit 7. LD roller shaft, ASF unit

Note: This order has no relevance to the order in the figure above.

ASF home position is sensed by the detection wheel attached to the right end of the LD (load) roller shaftand the ASF HP sensor. The detected condition is fed back to IC2 E05B33CB. The ASF motor is controlledbased on the home position detected by the ASF HP sensor. A 4-phase/48-pole PM-type pulse motor isused for the pump motor, which is controlled by a constant-current bipolar drive. The current control signalfor each phase and phase control signal output from the IC2 gate array E05B33CB are converted into pumpmotor control signals by the IC6 bipolar driver UDN2917EB to control the PF motor. Table 2-6 and Table 2-7show pump motor specifications and pump motor drive frequency, respectively.

Item Description

Motor type 4-phase / 48-pole / PM-type pulse motor

Drive voltage 42 VDC 5% (Voltage applied to the driver)

Coil resistance 9.3 10%, at 77 F (25 C) per phase



Minimum step 1/218 inch / pulse (2-2 phase drive)

Combination Gear

(12 mm, 20.8 mm)

Combination Gears

(12 mm, 26 mm)

Gear (27.2 mm)

Gear (16.8 mm)

Combination Gears

(14.4 mm, 21.6 mm)

Change Cam Gear (16 mm)

(Slider Mechanism)Combination Gear(12 mm, 15 mm)

Slider Shaft

Gear (11.5 mm)

Pump Motor

Pump MotorPinion Gear

5

4

3

Figure 2-8. ASF Mechanism

Table 2-6. Pump Motor Specifications

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Mode Frequency Pulse Feeding Acceleration Steps Deceleration Steps

Intervals Speed W1-Phase 1-2 Phase W1-Phase 1-2 Phase

Paper feedback 436 2294 2/sec. 5 5

ASF Multi Feed Prevention Mechanism

The paper loading assembly in the ASF is composed of a D-cut paper loading roller, a C-cut cam, apaper feedback lever, and a pinch roller. The C-cut cam and the D-cut roller move synchronously,because they are on the same shaft. When they rotate counterclockwise (viewed from the right), thepaper feedback lever moves along with the notch in the C-cut cam to push dislocated paper back up tothe standby position. It is called dislocation when multiple sheets, including the paper to be loaded inthe next rotation, slip out of standby position and fall into the paper path.

ASF Multi Feed Prevention Mechanism Operating Principles

1. When you press LOAD/EJECT or input a print order at the PC, the PF motor rotatescounterclockwise and makes the C-cut cam rotate in the same direction.

2. The paper feedback lever clutched to the C-cut cam rises with the counterclockwise rotation to catchslipped paper. With this motion, the pad is pushed back, and the pinch roller and D-cut paper loadingroller move to a position where there is no friction.

3. When dislocated paper is pushed back up to standby position by the paper feedback lever,counterclockwise rotation of the pump motor releases the hopper release lever and the D-cut paperfeed roller begins to load the paper.

4. When the ASF finishes feeding the paper to the specified position, the f lat part of the D-cut paper

loading roller turns around to the paper path side, where the D-cut paper loading roller loses contactwith the paper and the pinch roller supports the paper instead. The paper pinch roller continues tosupport the paper until it is completely ejected from the ASF by rotation of the PF roller. The paperfeedback lever, during this movement, is in the standby position, as shown in the above left figure.

Table 2-7. Pump Motor Drive Terms

D-Cut PaperLoading Roller C-Cut Cam

Pinch RollerHopper

Hopper Spring

Pad SpringPaper Feedback Lever

Figure 2-9. ASF Multi Feed Prevention Mechanism

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2.2.7 Ink System

The ink system for this printer absorbs and ejects ink, cleans the printhead surface, and caps the printheads.It is composed of the following:

Ink cartridgePump mechanismWiping mechanismCapping mechanismWaste ink drain pads

This section describes operational principles of the pump mechanism and capping mechanism. The figurebelow shows the structure of the ink system.

Head Cleaner

PumpMotor

Combination Gear(12 mm, 26 mm)

Combination Gear(14.4 mm, 21.8 mm)

Pump DriveShaft

Gear(21.6 mm)

Pump ReductionShaft

Pump 1 Pump 2

Clutch

Black Ink CartridgeCapping Mechanism

Wiping Mechanism

Waste Ink Drain Pads

Air Valves

Pump Mechanism

Color Ink Cartridge

Figure 2-10. Ink System

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2.2.7.1 Pump Mechanism

The functions of the pump mechanism, which is composed of the pump motor, slider mechanism, anddisengage mechanism, are absorbing black/color ink from the capping unit, false absorption, and setting andresetting the wiper. When the CR returns to CR home position, it pushes the slider in the slider mechanismto the right end. That movement engages the gear (16 mm) in the slider mechanism with the change cam inthe disengage mechanism. Then the change cam switches to the pump mechanism side when the pumpmotor rotates clockwise in the specified steps, and the drive from the pump motor is transmitted to the pumpmechanism. Torque is transmitted to the pump side via the disengage mechanism in the following order:

1. Disengage mechanism switch process.2. CR moves to home position.3. Slider moves the right end (slider mechanism).4. The gear (16 mm) engages the change cam (slider mechanism).5. The change cam switches to the pump side (disengage mechanism).6. The combination gear (14.4 mm, 21.6 mm) shifts to the right (disengage mechanism).

The following figure shows how the gears are engaged.

Combination Gear(12 mm, 20.8 mm) Combination Gear(14.4 mm, 21.6 mm) Combination Gear(12 mm, 26 mm)

Pump Motor Pinion Gear

Pump Motor

Gear (11.5 mm)

Slider Shaft

Pump Drive Shaft

Gear (21.6 mm)Combination Gear(12 mm, 15 mm)

Gear (16 mm)(Slider Mechanism)

Cam

Gear

(16.8 mm)

Gear(27.2 mm)

Pump Unit

Pump Reduction Gear

4

5

3

Figure 2-11. Pump Mechanism

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Transmission Process for Pump Motor Torque

1. Pump motor pinion gear 2. Combination gear (12 mm, 26 mm)

3. Combination gear (14.4 mm, 21.6 mm) 4. Pump drive shaft

5. Gear 21.6 6. Pump reduction shaft 7. Pump unit

Note: This order is irrelevant to the order indicated with arrows in Figure 2-11.

The pump unit switches functions, depending on the direction the pump motor rotates, as show in Table 2-8.

Motor Rotation Direction Function

Clockwise direction(Forward)

Absorption of color ink, false absorption of color ink,Micro absorption of color ink, resetting the wiper

Counterclockwise direction(Reverse)

Absorption of black ink, False absorption black ink,Micro absorption of black ink, setting the wiper

Note: The rotation direction is described when the motor is viewed from the pinion gear side.

Table 2-8. Pump Motor Rotation and Function

Wiper

Pump Motor

(Clockwise Direction)

Pump Motor(Counterclockwise Direction)

Color Capping

Waste Ink

Drain Pads

Color Pump Side

Wiper Reset

Color Capping

Color Ink Absorbed

Black Pump Side Black Pump Side

Color Pump Side

No Color Ink Absorbed

Black Pump Side

Wiper Set

Black Pump SideWaste InkDrain Pads

Black Ink Absorbed

Wiper

No Black Ink Absorbed

Black Capping

Black Capping

Figure 2-12. Pump Mechanism

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The pump motor for this printer also drives the ASF mechanism. See Table 2-6 for its specifications. Thedrive terms for the pump motor in pump mode are shown in Table 2-9.

Acceleration Steps Deceleration Steps

Absorption Mode Frequency PulseIntervals

W1-2Phase

2-2Phase

1-2Phase

W1-2Phase

2-2Phase

1-2Phase

High speed 1350 741 30 30

Normal speed 675 1481 18 18

Low speed 281 3559 0 0

Disengage 141 7092 0 0

2.2.7.2 Capping Mechanism

The capping mechanism caps printheads with the cap holder to prevent ink around the nozzles fromthickening while the printer is in standby or when printer power is off. There are two separate holders: onefor color ink and the other for black ink. When the CR moves from home position to the right side of the

printer (motion 1 in Figure 2-13), the holders move up to capping position (motion 2 in Figure 2-13) to capthe printheads. Also, when the CR unit moves to the right end of the CR shaft, the air valve shuts offcompletely (motion 3 in Figure 2-13).

The air valve is released and shut alternately for false absorption or absorption mode. (See Section 2.4.1 forthe details.) Since this printers power switch is in the secondary circuit, the capping operation is completelycarried out by constant voltage if printer power is turned off during the capping operation. The figure belowshows the capping mechanism.

Table 2-9. Pump Motor Drive Terms in the Pump Mode

Black Ink Cartridge Color Ink Cartridge

To the Drain Pads

Cap 1 Cap 2

Air Tubes

Air Valve2

1

32 2

Figure 2-13. Capping Mechanism

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2.3 Circuit Operating Principles

This printer consists of the following circuit boards:

C202 MAIN boardC202 PSB/PSE boardC202 panel board

In addition to the circuit boards above, printhead driver circuits are directly attached to the black head andthe color head in the CR unit. This section describes the operational principles of the C202 PSB/PSE boardand C202 MAIN board. Table 2-10 shows input voltages and applications.

2.3.1 C202 PSB/PSE Board

The power circuitry of this printer uses an RCC (ringing choke converter), which outputs two types of VDCnecessary to operate the printer.

VDC Application

+42 V MotorsPrinthead common voltage

+5 V C202 MAIN control board (logic)C202 panel boardSensors (HP sensor, ASF HP sensor, PE sensor)

The power switch for this printer is in the secondary circuit, allowing the PSB/PSE board to continue to

supply voltage for the power and logic lines for a minimum of 20 seconds, until the printhead returns to thecapping position, even if the printer is turned off during printing. This extra time prevents ink leakage anddrying in the printhead that could be caused by leaving the printhead uncapped.

AC voltage from the AC inlet is first input to a filter circuit for higher harmonics absorption and is then inputto a rectification and smoothing circuit, converting it into DC voltage. This DC voltage is then input to theswitching circuit. An FET on the primary side performs this switching operation and generates a +42 voltagethat is stabilized on the secondary side and then converted into a stable +5 VDC by a chopping regulator IC.Figure 2-15 shows a block diagram for the electrical circuitry.

C202 PSB/PSE BoardC202 PNL Board

C202 MAIN Control Board

CR Motor

PF Motor

Pump Motor

Color Head

Driver Circuit

Black Head

Driver Circuit

Sensors

Printer Mechanism

+42 VDC

+5 VDC

Figure 2-14. Circuit Block Diagram

Table 2-10. DC Voltage Distribution

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The operating principles for the various protection and controller circuits shown above are described below.

+5 VDC line over voltage protection circuit

The output voltage level of +5 V is monitored by a Zener diode (ZD53) in the secondary circuit. If thevoltage level exceeds 9 V, switching FET Q1 goes OFF, no induced voltage is generated, andproduction of the +5 VDC and +42 VDC stops as a result. The circuit operates as follows:

Zener diode (ZD53) detects a voltage exceeding +9 V on the +5 V line.Transistor Q81 goes ON.Photo coupler PC1 goes ON.FET Q31 goes ON, and the gate current for switching FET Q1 is cut OFF.Switching FET Q1 goes OFF.

+5 VDC line constant voltage control circuit / +5 VDC line over current protection circuit

Voltage and current on the +5 VDC line are monitored by regulator IC51. Abnormal voltage or current onthe +5 VDC line are detected, and the information is fed back to the +5 V comparator in the IC. Then the+5 VDC is controlled or cut off.

+42 VDC line over voltage protection circuit

The output level of the +42 VDC line is monitored by two Zener diodes: ZD52 and ZD87. When theoutput level of the +42 VDC line exceeds +48 V, switching FET Q1 goes OFF in the following sequence:

Zener diodes (ZD52, ZD87) detect a voltage over 48 V on the +42 V line.

Transistor Q81 goes ON.

Photo coupler PC1 goes ON.

FET Q31 goes ON, and the gate current for the switching FET Q1 is cut OFF.

Switching FET Q1 goes OFF.

Primary Circuit Secondary Circuit

Full WaveRectifier Circuit

Filter Circuit

SmoothingCircuit

SwitchingCircuit

AC Input

SmoothingCircuit

PhotoCoupler

+5V Switching Regulator

+5V Constant Voltage Control Circuit

+5V Over Current Protection Circuit

+42V Constant CurrentControl Circuit

+5V Over VoltageProtecion Circuit

+42V Over VoltageProtection Circuit

+42V Over CurrentProtection Circuit

Power Off Delay Circuit

Power Switch

+42V

+5V

PhotoCoupler

Figure 2-15. VDC Circuit Block Diagram

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+42 VDC line constant voltage control circuit

Voltage on the +42 VDC line is monitored by Zener diodes ZD51 and ZD81 to ZD86. When the voltageon the +42 VDC line exceeds 38 V, switching FET Q1 is controlled in the following sequence:

Zener diodes (ZD52 and ZD81 to ZD86) detect the voltage over 38 V on the +42 VDC line.Transistor Q81 goes ON.

Photo coupler PC1 goes ON.Transistors Q3 and Q2 go OFF, and gate current for the switching FET Q1 is cut OFF.Switching FET Q1 goes OFF.When the voltage level drops under +38 V, photo coupler PC1 and transistors Q3 and Q2 goOFF and switching FET Q1 goes back ON.

+42 VDC line overcurrent protection circuit

The output current is monitored by transistors Q81 and Q82. When the output voltage is abnormally low,this information is fed back to the primary circuit v ia the photo coupler PC1 to stop the switchingoperation.

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2.3.2 C202 MAIN Control Board

C202 MAIN control board consists of the following:

Logic circuits for the PROM, DRAM, CPU, ASIC, and EEPROMMotor control and driver circuits for the CR motor, PF motor, and pump motor

Head control/ driver circuits for the black and color headsOther circuits for the I/F (parallel I/F, Mac serial, Type B I/F), sensors, RTC timers, and reset

Figure 2-16 shows the circuit block diagram for the main control board.

C202 MAIN Control Board

IC3 IC7 IC5

P-ROM (4M)CG-ROM

(16M)DRAM (4M)

C202 PNL Board

C202 PSB/PSEBoard

+42 V +5 V

IC1CPU

IC2Gate Array

Black InkDriver Circuit

Color HeadDriver Circuit

BlackInk Cartridge

ColorInk Cartridge

IC11EEPROM

IC20Timer IC

IC16PF MotorDriver

IC13CR MotorDriver

IC6Pump MotorDriver

IC15Mac Serial I/FTranceiver IC

IC12Parallel I/F IC

Type B I/F

HPSensor

HPSensor

PESensor

CR Unit

Address BusData Bus

IC8+42 V LineReset IC

IC95 V LineReset IC

CommonDriver

CommonDriver

Figure 2-16. C202 MAIN Board Block Diagram

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Table 2-11 shows the functions allocated for the CPU and gate array.

IC Location Function

CPU IC1

Sets the current value for each motor.Outputs the driving trigger pulse for each motor.Outputs the driving trigger pulse for each head.Outputs the system clock.Inputs the resistance value for the thermistor.Inputs an ON/OFF signal indicating theinstallation status for each cartridge.Transfers data received from the I/F to theDRAM.Controls interruption signals.

Gate Array IC2

Controls motor drivers.Controls print data for each head.Controls data from I/F and transfers it to theCPU.Outputs head driver control pulses.

Counts the dot numbers used for printing.Controls voltages for EEPROM, control panel,timers, and heads.

Table 2-11. Functions Allocated for the CPU and the Gate Array

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2.3.2.1 Printhead Driver Circuit

The printhead driver circuits, built in separately on the black and color heads, consist of the common drivers(black head, IC17; color head, IC18) on the C202 MAIN board and nozzle selectors (black head, IR2C72C;color head, IR2C73C) on the head driver boards. Each common driver produces trapezoidal pulsesaccording to signals sent from gate array IC2, and transfers them to the nozzle selector on the head driverboard. Print data is converted into serial data in the gate array and is then transferred to the nozzle selectoron the head driver board to select the nozzles to activate. The PZT common lines are selectively drivensimultaneously, based on the driver waveform produced by the common driver to activate nozzles selectedby the print data.

Common Driver Circuit for the Black Head

Common driver IC17 HBD2813C produces trapezoidal waveforms by combining six signals (BCHG,BND1, BND2, BMD1, BMD2, and BKC) output from gate array IC2 E05B33CB, using the VM voltage asa basis. There are seven different types of trapezoidal waveforms produced for normal dot mode, Microdot mode, and so on, and each form varies, depending on the width of the combined signals. The risingform is determined by the BCHG and BKC signals, regardless of the print mode. The falling form isdetermined by two different pairs of signals: BND1 and BND2 in normal dot mode; and BMD1 andBMD2 in Micro dot mode. The VH voltage adjustment value stored in the EEPROM, which is unique toeach head, is read into the gate array, and then transferred as 8-bit serial data via the CBDATA signal to

be set in the common driver. By this procedure, internal resistance is determined, and the driverwaveform is adjusted as a result.

E05B33CB

IC 2

HBD2813C

BCHG 68BKC 61

BND1 67BND2 66BMD1 63BMD2 62

SBDATA 75SCLK 79

+42 V

BHCLK 87BHLAT 86

BBHDATA 89

BAHDATA 90

IC 18

HBD2813C

CKC 69CCHG 74

CND1 73CND2 72CMD1 71CMD2 70

SCDATA 76

CHCLK 95CHLAT 94

YHDATA 99MHDATA 98CHDATA 97

+5 V

VHPR 82 VH

VH

IR2C72C

IR2C72C

BCLKBLATBSI2

BSI1

CCLKCLATCSI3

CSI1

Gate Array

Common Driver(Black Head)

Common Driver(Color Head)

C202 MAIN Board

IC 17CommonSignal

Black Printhead Driver Board

Color Printhead Driver Board

Black HeadDriver Waveform

NozzleSelector

NozzleSelector

CN9

CN10VDD (+5 V)

VDD (+5 V)

IR2C73CNozzleSelector

CSI2VH

CLATCCLKVDD

CommonSignal

Color HeadDriver Waveform

Figure 2-17. Printhead Driver Circuit Diagram

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Black Head Nozzle Selector Circuit

Print data is input from data input ports D0 to D15 in gate array IC2 E05B33CB into the gate array to be

converted into serial data and output to the nozzle selector from ports BBHDATA and BAHDATA. Data isthen separated into two sides through ports BBHDATA and BAHDATA, which are allocated with two linesof black nozzles; the lines #1, #3 and #2, #4, respectively. The smaller-numbered nozzle on each linereceives data faster. Data is transferred from IC2 gate array to nozzle selector IC IR2C72C at 64-bit /2.5 MHz, synchronizing with the BHCLK (clock signal) and BHLAT (latch signal). The ON/OFF status ofeach nozzle in the nozzle selector is determined based on the data transferred.

Common Driver Circuit for the Color Head

The circuit structure for the color head is basically the same as for the black head. Common driver IC18HBD2813C produces trapezoidal waveforms by combining six signals (CCHG, CND1, CND2, CMD1,CMD2, and CKC) output from gate array IC2 E05B33CB. There are seven different types of trapezoidalwaveforms produced for normal dot mode, Micro dot mode, and so on, and each form varies, depending

on the width of the combined signals. The rising form is determined by CCHG and CKC, regardless ofthe print mode. The falling form is determined by two different pairs of signals: CND1 and CND2 innormal dot mode; and CMD1 and CMD2 in micro dot mode. The VH voltage adjustment value stored inthe EEPROM, which is unique to each head, is read into the gate array, and then transferred as 8-bitserial data via the SBDATA signal to be set in the common driver. By this procedure, internal resistanceis determined and the driver waveform is adjusted as the result.

LATNCHG

BCHG

BND1

BND2

BMD1

BMD2

BKC

Head Drive Waveform

Figure 2-18. Waveform Producing Process for Black Nozzles

LATNCHG

CCHG

CND1

CND2

CMD1

CMD2

CKC

Head Drive Waveform

Figure 2-19. Waveform Producing Process for Color Nozzles

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Color Head Nozzle Selector Circuit

Print data is input from data input ports D0 to D15 in gate array IC2 E05B33CB into the gate array to beconverted into serial data, and output to the nozzle selector from ports YHDATA, MHDATA, andCHDATA, depending on the color. Data is then allocated to the corresponding nozzle lines, alternatingtwo lines: from #1 to #2. Data is transferred from gate array IC2 to nozzle selector IC IR2C72C at 64-bit

/ 2.5 MHz, synchronizing with the CHCLK (clock signal) and CHLAT (latch signal). The ON/OFF status

of each nozzle in the nozzle selector is determined based on the data transferred.

2.3.2.2 Reset Circuits

The C202 MAIN board contains two reset circuits; for logic line (+5 V) and power line (+42 V). The voltagesfor +5 V and +42 V in each reset circuit are monitored to prevent printer malfunctions caused by abnormalvoltage levels. When an abnormal condition is detected, a reset signal is sent to the CPU to reset the CPUand the gate array. The function of the reset circuit is described below.

Reset Circuit for the +5 V Line

The +5 V reset circuit monitors the voltage level for the +5 V line at the 3 VCC port of IC9 PST592D,and outputs a reset signal from port 1 VOUT to the CPU gate array when it detects an abnormal voltage

level. IC9 is energized under the conditions below.When the printer is turned ON, a reset signal is output for 100 ms after the +5 V line voltage levelrises to 4.2 V.

During printing, when the 5 V line voltage level drops under 4.2 V, a reset signal is output. The resetsignal does not go OFF until 100 ms passes after the +5 V line voltage level recovers to 4.2 V, asdescribed above.

IC1CPU 23 RESET81RES

27 MRES

IC9

+5V +5V

R29 1K

Reset IC for +5V line

Gate arrayIC2

VOUT 1MRES 2VCC 3GND 4

Figure 2-20. Reset Circuit for the +5 VDC Line

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Reset Circuit for the +42 V Line

The +42 V reset circuit monitors the voltage level of 42 V line at the 3 VCC port of IC8 M51955D, andfeeds back the information on power ON/OFF status to the CPU based on the detected voltage. Whenthe +42 V line drops under +33.2 V, IC8 detects the power off status and outputs a reset signal from port6 to CPU port 82 NMI via the OR circuit of IC19. When the voltage level recovers to 32.2 V, port 6 of

IC8 stops outputting the signal, which is detected by port 78 of the CPU.

IC1CPU 23 RESET

81RES

27 MRES

IC8

NC8 8VCC 7OUT 6NC5 5

1 NC12 IN3 NC34 GND

+42V

R11120K1%

R124.65K1%

78 P21

82 NMI

+5V

+5V

IC19

12 4

TC7S32F

R7810K

113

LED4

Reset IC for +42V line

Gate ArrayIC2

C150.1U

Figure 2-21. Reset Circuit for the +42 VDC Line

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2.3.2.3 Motor Driver Circuits

This printer has three motors: the CR motor, PF motor, and pump motor. Since they are all driven by IC13(UDN2917EB), they use the same control system.

CR Motor Driver Circuit

The phase control signal for the CR motor is converted into the UDN2917EB micro-step bipolar driversystem by gate array IC2. Then it is output from port 55 to ports 43 and 26 on IC13 UDN2917EB. IC13determines the phase mode based on the signal sent. The current control signal is also produced in gatearray IC2 and output from ports 51 to 54 to ports 1, 2, 23, and 24 on IC13 UDN2917EB.

PF Motor Driver Circuit

The motor driver circuit for the PF motor is the same as for the CR motor.

Pump Motor Driver Circuit

The motor driver circuit for the pump motor is the same as for the CR motor.

Data Bus

IC2

1 CR A

3 CR-A

2 CR B

4 CR-B

IC1

CPU

CRA0

CRA1

CRB0

CRB1

CRAPH

CRBPH

5152

53

54

5556

DA1112

CRTRG198

Gate Array

CR Motor

18

21

AA

B

B

I10

I11

I20

I21

PH1PH2

VREF1VREF2

2

23

24

4326

4425

UDN2917EBIC13

163

Figure 2-22. CR Motor Driver Circuit

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2.3.2.4 Sensor Circuits

The sensors for this printer are:

3 photodiode sensors: HP sensor, ASF HP sensor, PE sensor2 mechanism switch sensors: Black and color cartridge sensors

1 thermistor for the color head

HP Sensor

The HP sensor, mounted on the upper right end of the top frame, determines the CR home position.When the CR returns to the home position, the detector plate attached to the back of the CR unit cuts inbetween sensor terminals, and a HIGH signal is output to the CPU. A LOW signal is then output to theCPU when the CR leaves the home position.

ASF HP Sensor

This sensor is mounted on the left end of the ASF to detect ASF home position. While the printer is instandby after printer power is turned on, the ASF is controlled to be located in ASF home position, whichmeans the ASF is ready to load paper. ASF HP position is detected by the ASF HP sensor and the ASFdetector wheel attached to the left end of the LD roller. A small portion of the ASF HP detector wheel

has a cutout, and when the cutout comes into position between the photo diode terminals, ASF homeposition is detected. Then, a LOW signal is output to the CPU. When the cutout leaves home position,the ASF detector wheel cuts in between photo diode terminals, and a HIGH signal is output.

PE Sensor

The PE sensor, mounted on the bottom right end of the top frame in the printer mechanism, detects apaper end. A paper end is detected when the detector plate on the PE sensor lever cuts in between thephotodiode terminals, and a HIGH signal is output to the CPU. When paper is loaded, it pushes up thePE sensor lever. With this motion, the detector plate, along with the PE sensor lever, is held up so that itdoes not fall between diode terminals, and a LOW signal is output to the CPU.

Ink Cartridge Sensor

An ink cartridge sensor built into each printhead determines whether a black or color ink cartridge isinstalled. An installed cartridge presses the sensor plate down, connecting two terminals on theprinthead driver board. Then a LOW signal is output to the CPU. If no cartridge is installed, the sensorplate loses contact with the terminals on the head driver board, and a HIGH signal is output to the CPU.

Printhead Thermistor

A printhead thermistor is attached directly to the color printhead driver board. The printer refers to thethermistor signal, which indicates the temperature around the printhead and feeds back the informationto CPU analog port 105. This information lets the printer control the head drive discharge voltage pulse,

based on the ink viscosity. The normal resistance for this thermistor is 10K 10% at 77 F (25 C).

SWA0

SWC0

SWC1

57

59

60

+5V

+5V

+5V

+5V

+5V

+5V

105AN0

IC1CPU

P41

P42

106

107

Head Thermistor

Black Ink CartridgeSensor

Color Ink CartridgeSensor

Data BusIC2Gate Array

HP Sensor

ASF HP Sensor

PE Sensor

Figure 2-23. Sensor Circuits

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2.4 Ink System Management

This section explains how the ink system is controlled to protect the printheads and ink supply and ensurehigh-quality output. This printer has several ink system control sequences, which vary for combinations ofbasic ink system operations. The printer selects the most suitable sequence by referring to printer

information, such as values for the timers and counters stored in the EEPROM, flags, and numbers ofsensor signals. This section describes basic ink operations, timers counters, and ink sequences.

2.4.1 Ink System Operations

The basic ink system operations are as described below.

Rubbing

This operation rubs the printhead surface against the felt part of the head cleaner (left half of the blade)in the pump unit by moving the CR from left to right. The printer does this to eliminate ink and dust onthe printhead surface to regain normal ink ejection and ensure firm head capping. A small amount of inkis sent to the nozzle surface before the rubbing operation to make adhering objects come off easily.

WipingThis operation moves the CR from right to left to rub the printheads against the rubber part of the headcleaner (right half of the blade) in the pump unit. The printer does this prior to ink absorption to eliminateink and dust on the printheads to regain normal ink ejection and ensure firm head capping.

Ink Absorbing

This operation draws ink out of the ink cavities by rotating the pump for both black and color heads usingthe specified steps while the head surfaces are capped and the air valves closed. The printer does thisto eliminate the ink that has increased viscosity and bubbles around the nozzles.

False Absorbing

This operation removes ink remaining inside the caps by rotating the pump for black and color headsusing the specified steps while the head surfaces are capped and the air valves open. This removes inkfrom the nozzle plate by vacuuming and ejecting ink remaining after the Ink absorbing and flushingoperations.

Micro Absorbing

This operation absorbs ink from the ink cavity by rotating the pump for black and color using thespecified steps while the head surfaces are capped and the air valves open. This sensitive operationeliminates bubbles formed in the ink cavities during the Ink absorbing operation.

Flushing

This operation ejects a specific amount of ink from the head when the CR moves to the false absorbingposition. This is done to prevent increases in ink viscosity. There are three types of flushing, as listedbelow.

Numbers of Shots Driver Waveform

Power flushing 4000 shots + 2 V, maximum 36 V for the correct voltage of thenormal dot

Periodic flushing 36 shots Waveform for the normal dot

Cleaning flushing 1400 shots Waveform for the normal dot

Table 2-12. Flushing Specifications

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Micro Vibration

Micro vibration is done to prevent ink from increasing in viscosity. The printer micro vibrates the ink inthe cavity by applying a driver voltage and pulse that vibrates the piezo elements. The printer only doesthis while the CR motor is accelerating to move the CR for printing.

2.4.2 Timers and Counters

This printer has a number of timer counters, soft counters, and flags. Their values, usually stored in theEEPROM, are the basis for selecting the ink sequence to be performed.

CL Timer (set individually for black and color ink)

The CL timer manages auto cleaning. It remains active while printer power is off and is reset whencleaning done.

Accumulated Printing Timer (set individually for black and color ink)

This timer adds up the amount of time spent printing. The value of this timer is not cleared after printerpower off. The timer is activated when the head is uncapped and pauses its adding when the printer

goes into the wait state. The value of this counter is reset when an ink absorbing operation is done.

Power Off Timer

This timer monitors how long printer power is off.

Ink Counter RB, Ry (set individually for black and color ink)

This counter monitors the amount of ink used in the cap during flushing. The value is stored after printerpower is turned off. When the value exceeds a specified value, the printer performs false absorbing andthen resets the counter.

CL2 Counter KKb, Kky (set individually for black and color ink)

The printer uses this counter value to determine the order of manual cleaning cycles run through thecontrol panel. Cleaning is usually performed in the order CL1, CL1, and CL2. This printer, however,does not necessarily follow this order, depending on the number of pages printed since the last cleaning.(See the description of the cleaning cycles in Section 2.4.3 on the next page.)

Protect Counter A

This counter monitors the total amount of ink drained to the waste ink drain pads. When the valueexceeds a specified amount (the counter value = 49000), a maintenance error occurs. The counter isreset by the EEPROM reset operation.

Ink Consumption CounterCb, Cy, Cm, Cc (set individually for black and color ink)

Each counter measures the ink consumed through printing, cleaning, and flushing after an ink cartridgeis installed. The printer or the EPW indicates an INK LOW or INK END based on the counter value.Even if the printer is turned off before a cleaning sequence completes, the printer regards the job as a

full cleaning and adds the specified value for the cleaning to the consumption counter. The counter isreset only when a cartridge is removed in cartridge replacement mode, which is selected on the controlpanel.

Black Ink Cartridge Color Ink Cartridge

INK LOW counter 37.6 107

dots 17.2 107

dots

INK END counter 41.6 107

dots 19.2 107

dots

Table 2-13. Ink Consumption Counter

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2.4.3 Ink System Sequences

The ink system sequences in this printer are combinations of basic ink system operations described inSection 2.4.1. The printer selects the most suitable ink sequence based on information provided by variouscounters, timers, and flags. The major ink system sequences are described in this section.

Manual Cleaning

Manual cleaning is performed by pressing the CLEANING button on the control panel. The cleaningmode to be used is selected from the following 5 modes based on the CL2 counter value for KKB, Kky(cleaning selection counter) and the number of the pages printed after the last cleaning.

CL1 (normal cleaning mode): wiping, ink absorbing, micro absorbing, false absorbing.

CL1 (powerful cleaning mode): wiping, ink absorbing, micro absorbing, false absorbing. Thecombined operations are same as in CL1, except for the amount ofink consumed.

CL2 (powerful cleaning mode): wiping, rubbing, ink absorbing, micro absorbing, false absorbing.Every operation except rubbing is the same as in CL1. However, theamount of ink consumed is larger than in CL1.

CL3 (false cleaning mode): wiping, micro absorbing, false absorbing. The amount of inkconsumed is very little, since ink is not absorbed.

One-time CL: wiping, ink absorbing, micro absorbing, false absorbing. Thecombined operations are same as in CL1, but the amount of inkconsumed in this cleaning mode is the largest amount of ink.

The CL2 counter is used to determine the cleaning mode to be performed when the manual cleaning is

repeated. The counter resets if the printer is turned off. The printer normally follows the order CL1 CL1CL2. However, this can vary, depending on the conditions described below:

CL3 is selected if no image has been printed since the latest cleaning.CL1 is selected if more than 5 pages have been printed since the latest cleaning.CL1, CL1, or CL2 selection is based on the CL2 counter value for Kkb, Kky under the followingconditions:

5 or fewer pages have been printed since the latest cleaning, and the current ink cartridgeis a replacement for an old one that was removed after an INK END or INK LOW error.

One time CL is performed under the following conditions:5 or fewer pages have been printed since the latest cleaning, but the current cartridge is areplacement for one that was removed without an INK END or INK LOW error.

Timer Cleaning

This cleaning is done automatically, based on the value of the CL timer counter while printer power ison. The sequence, which has four separate modes (Timer CL1, Timer CL2, Timer CL3, and Timer CL4)for black and color ink, differs from manual cleaning modes. It does not include ink absorbing, but onlyuses wiping and micro absorbing operations. Therefore, little ink is consumed compared to manualcleaning.

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Power ON Sequence

During this sequence, the printer does the following:

Refers to protect counter A.Resets CL2 counter Kkb, Kky.Checks if ink cartridges are installed.

Checks consumed ink amount.Performs necessary cleaning, based on the conditions such as initial charging, HP status, thepower off timer, and CL timers.Resets the power off timer.

Cartridge Replacement Sequence

The printer determines which ink cartridge (black or color) needs replacing during the cartridgereplacement CL sequence, based on conditions such as cartridge installation, INK LOW, and INK END.The cartridge replacement CL sequence consists of wiping, ink absorbing, micro absorbing, and falseabsorbing. It consumes less ink than the manual cleaning sequence. (If the initial charge flag is notdetected during this operation because the printer is new, the printer enters initial ink charge sequence,instead.)

During the cartridge replacement sequence, the one-time flag is reset or set in the EEPROM, dependingon the amount of ink consumed in the removed cartridge. (If 50% was used or not.) This flag indicateswhether the cartridge was removed because of an INK END error or by accident. The printer stores thisinformation in the EEPROM to refer to when selecting the manual cleaning mode to carry out. If lessthan 50% ink was consumed in the ink cartridge that was removed from the CR unit, the one-time flag isset in the EEPROM, and one-time cleaning is carried out as the first manual cleaning operation aftercompletion of the cartridge replacement sequence.

Initial Charge Sequence

The printer performs wiping, rubbing, ink absorbing, micro absorbing, and false absorbing during theinitial charge sequence. This sequence is performed according to the status of the initial charge flag.This sequence consumes a large amount of ink (about 20 % of total ink amount) and requires

approximately seven minutes to execute. The CL timers for each color, accumulated printing timer,initial ink charge flag, and one-time flag are reset at the completion of this sequence.

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