Text preview for : Epson Stylus Color 760 Service Manual.pdf part of Epson Stylus Color 760 Epson Stylus Color 760 Color ink jet printer Service Manual
Back to : Epson Stylus Color 760 Se | Home
SERVICE MANUAL
Color ink jet printer
EPSON Stylus COLOR 760
®
SEIJ99004
EPSON Stylus COLOR 760
Revision C
Notice:
n All rights reserved. No part of this manual may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SEIKO EPSON CORPORATION. n The contents of this manual are subject to change without notice. n All effort have been made to ensure the accuracy of the contents of this manual. However, should any errors be detected, SEIKO EPSON would greatly appreciate being informed of them. n The above not withstanding SEIKO EPSON CORPORATION can assume no responsibility for any errors in this manual or the consequences thereof. EPSON is a registered trademark of SEIKO EPSON CORPORATION.
General Notice:
Other product names used herein are for identification purpose only and may be trademarks or registered trademarks of their respective owners. EPSON disclaims any and all rights in those marks.
Copyright © 1999 SEIKO EPSON CORPORATION. Printed in Japan.
2
EPSON Stylus COLOR 760
Revision C
PRECAUTIONS
Precautionary notations throughout the text are categorized relative to 1)Personal injury and 2) damage to equipment.
DANGER
Signals a precaution which, if ignored, could result in serious or fatal personal injury. Great caution should be exercised in performing procedures preceded by DANGER Headings. Signals a precaution which, if ignored, could result in damage to equipment.
WARNING
The precautionary measures itemized below should always be observed when performing repair/maintenance procedures.
DANGER
1. ALWAYS DISCONNECT THE PRODUCT FROM THE POWER SOURCE AND PERIPHERAL DEVICES PERFORMING ANY MAINTENANCE OR REPAIR PROCEDURES. 2. NOWORK SHOULD BE PERFORMED ON THE UNIT BY PERSONS UNFAMILIAR WITH BASIC SAFETY MEASURES AS DICTATED FOR ALL ELECTRONICS TECHNICIANS IN THEIR LINE OF WORK. 3. WHEN PERFORMING TESTING AS DICTATED WITHIN THIS MANUAL, DO NOT CONNECT THE UNIT TO A POWER SOURCE UNTIL INSTRUCTED TO DO SO. WHEN THE POWER SUPPLY CABLE MUST BE CONNECTED, USE EXTREME CAUTION IN WORKING ON POWER SUPPLY AND OTHER ELECTRONIC COMPONENTS.
WARNING
1. REPAIRS ON EPSON PRODUCT SHOULD BE PERFORMED ONLY BY AN EPSON CERTIFIED REPAIR TECHNICIAN. 2. MAKE CERTAIN THAT THE SOURCE VOLTAGES IS THE SAME AS THE RATED VOLTAGE, LISTED ON THE SERIAL NUMBER/RATING PLATE. IF THE EPSON PRODUCT HAS A PRIMARY AC RATING DIFFERENT FROM AVAILABLE POWER SOURCE, DO NOT CONNECT IT TO THE POWER SOURCE. 3. ALWAYS VERIFY THAT THE EPSON PRODUCT HAS BEEN DISCONNECTED FROM THE POWER SOURCE BEFORE REMOVING OR REPLACING PRINTED CIRCUIT BOARDS AND/OR INDIVIDUAL CHIPS. 4. IN ORDER TO PROTECT SENSITIVE MICROPROCESSORS AND CIRCUITRY, USE STATIC DISCHARGE EQUIPMENT, SUCH AS ANTISTATIC WRIST STRAPS, WHEN ACCESSING INTERNAL COMPONENTS. 5. REPLACE MALFUNCTIONING COMPONENTS ONLY WITH THOSE COMPONENTS BY THE MANUFACTURE; INTRODUCTION OF SECOND-SOURCE ICs OR OTHER NONAPPROVED COMPONENTS MAY DAMAGE THE PRODUCT AND VOID ANY APPLICABLE EPSON WARRANTY.
3
EPSON Stylus COLOR 760
Revision C
PREFACE
This manual describes basic functions, theory of electrical and mechanical operations, maintenance and repair procedures of the EPSON Stylus COLOR 760. The instructions and procedures included herein are intended for the experienced repair technicians, and attention should be given to the precautions on the preceding page. The chapters are organized as follows:
CHAPTER 1. CHAPTER 2. CHAPTER 3. CHAPTER 4.
PRODUCT DESCRIPTIONS OPERATING PRINCIPLES TROUBLESHOOTING DISASSEMBLY AND ASSEMBLY
Provides a general overview and specifications of the product.
Describes the theory of electrical and mechanical operations of the product.
Provides the step-by-step procedures for troubleshooting.
Describes the step-by-step procedures for disassembling and assembling the product.
CHAPTER 5. CHAPTER 6.
ADJUSTMENTS MAINTENANCE
Provides Epson-approved methods for adjustment.
Provides preventive maintenance procedures and the lists of Epson-approved lubricants and adhesives required for servicing the product.
APPENDIX
Provides the following additional information for reference: · EEPROM Address Map · Connector Pin Assignments · C298MAIN Board Component Layout · Parts List and Explode Diagrams · C298MAIN Board Circuit Diagram
4
EPSON Stylus COLOR 760
Revision C
Revision Status
Revision A B Issued Date August 17, 1999 October 5, 1999 Description First Release Second release Change has been made due to overall review of the manual. Third Release Change has been made due to overall review of the manual. · Some T.B.D have been made clear. · Appendix has additional information. - Fig7-3, 7-4 has been mounted.
C
November 25,1999
5
EPSON Stylus COLOR 760
Revision C
Envelopes ....................................................................................................... 23 INK CARTRIDGE ....................................................................................... 24 Black Ink Cartridge ............................................................................................ 24 Color Ink Cartridge ............................................................................................. 24
PRODUCT DESCRIPTION
FEATURES ................................................................................................... 7 SPECIFICATIONS ........................................................................................ 8 Physical Specification ........................................................................................... 8 Printing Specification ........................................................................................... 8 Paper Feeding ....................................................................................................... 8 Input Data Buffer .................................................................................................. 8 Electric Specification ............................................................................................ 9 Environmental Condition .................................................................................... 10 Reliability ........................................................................................................... 10 Safety Approvals ................................................................................................ 10 Acoustic Noise .................................................................................................... 10 CE Marking ........................................................................................................ 10 INTERFACE ............................................................................................... 11 Parallel Interface (Forward Channel) ................................................................. 11 Parallel Interface (Reserve Channel) .................................................................. 14 USB Interface ..................................................................................................... 15 Preventing Data Transfer Time-out of Hosts ...................................................... 16 Interface Selection .............................................................................................. 16 IEEE1284.4 Protocol .......................................................................................... 16 OPERATOR CONTROLS ........................................................................... 17 Operating Switch ................................................................................................ 17 Control Panel ...................................................................................................... 17 Switches .......................................................................................................... 17 Indicators ........................................................................................................ 17 Panel Functions ................................................................................................... 18 Printer Condition and Panel Status ..................................................................... 19 Printer Initialization ............................................................................................ 19 Errors .................................................................................................................. 20 PAPER ......................................................................................................... 21 Paper Handling ................................................................................................... 21 Paper Specification ............................................................................................. 21 Cut Sheet ........................................................................................................ 21 Transparency, Glossy Paper ........................................................................... 21 Envelope ......................................................................................................... 21 Index Card ...................................................................................................... 21 Printing Area ....................................................................................................... 22 Cut Sheet ........................................................................................................ 22
Operating Principles
Overview ...................................................................................................... 28 Printer Mechanism .............................................................................................. 28 Printing Mechanism ....................................................................................... 29 Printing Process .............................................................................................. 30 Carriage Mechanism ...................................................................................... 31 Platen Gap (PG) Adjust Mechanism .............................................................. 32 Paper Feeding Mechanism ............................................................................. 32 CR Lock Mechanism ...................................................................................... 34 Paper Loading Mechanism ............................................................................. 35 Pump Mechanism ........................................................................................... 37 Capping Mechanism ....................................................................................... 39 Electrical Circuit Operating Principles ......................................................... 40 C298PSB/PSE Board .......................................................................................... 41 C298MAIN Board .............................................................................................. 43 Printhead Driver Circuit ................................................................................. 45 Reset Circuit ................................................................................................... 46 CR Motor Driver Circuit ................................................................................ 47 PF Motor Driver Circuit ................................................................................. 49 EEPROM Control Circuit .............................................................................. 50 Sensor Circuit ................................................................................................. 51
Troubleshooting
Overview ...................................................................................................... 54 Troubleshooting with LED Error Indications ..................................................... 55 Remedies for Paper Out Error ........................................................................ 57 Remedies for the Paper Jam Error .................................................................. 59 Remedies for No I/C and Ink Out Errors ....................................................... 60 Remedies for the Maintenance Error ............................................................. 62 Remedies for Fatal Error ................................................................................ 63 Isolating the Faulty Part on the Power Supply Board ........................................ 65 Isolating the Faulty Part according to the Phenomenon ..................................... 67
25
EPSON Stylus COLOR 760
Revision C
Head Angular Adjustment ............................................................................ Bi-D Adjustment .......................................................................................... USB ID input ................................................................................................ Initial Ink Charge Operation ........................................................................ Head Cleaning Operation ............................................................................. Protection Counter Check/Reset .................................................................. Recovery for the clogged nozzle .................................................................. Print A4 pattern ............................................................................................ 123 126 129 133 134 135 137 138
Disassembly and Assembly
Overview ...................................................................................................... 73 Precautions for Disassembling the Printer .......................................................... 73 Tools ................................................................................................................... 74 Screw Specifications ........................................................................................... 75 Service Checks After Repair .............................................................................. 76 Disassembly Procedures ............................................................................... 77 Removing the Upper Housing ............................................................................ 78 Removing the Circuit Board Assembly .............................................................. 79 Removing the Operation Panel ........................................................................... 81 Disassembling the Printer Mechanism ............................................................... 82 Removing the Printhead Unit ......................................................................... 83 Removing the Waste Ink Absorber Tray Assembly ....................................... 85 Removing the Ink System Assembly ............................................................. 87 Removing the CR Motor Assembly ............................................................... 90 Removing the ASF Assembly ........................................................................ 91
Removing the Paper Feed Roller Assembly ............................................................. 93 Removing the Right and Left LD Roller Assembly ..................................................97
PF Loop scale unit assembling procedure ................................................... 139 Assembling the PF Loop scale unit .................................................................. 139 Sticking the PF Loop scale unit to Gear 76 ...................................................... 141
Maintenance
Overview .................................................................................................... 143 Cleaning ............................................................................................................ 143 Service Maintenance ......................................................................................... 143 Lubrication ........................................................................................................ 144
Removing the CR Assembly .......................................................................... 98
Disassembling the CR Assembly............................................................................ 101
Removing the PF Roller & Paper Eject Roller Assy. ................................... 103 Remove the PF Motor Assembly ................................................................. 107 Removing the PE Detector Assembly .......................................................... 108
Appendix
Connector Summary .................................................................................. 153 Connector Pin Assignment ............................................................................... 153 EEPROM ADDRESS MAP ............................................................................. 156 Circuit Board Component Layouts ............................................................. 161 Exploded Diagram ..................................................................................... 164 Parts List ................................................................................................... 169 Circuit Diagrams ........................................................................................ 172
Adjustment
Overview .................................................................................................... 110 Required Adjustments ...................................................................................... 110 Adjustment Tools Required .............................................................................. 111 Adjustment ................................................................................................ 112 Parallelism Adjustment ..................................................................................... 112 Backlash value Adjustment for PF motor ......................................................... 115 Adjustment by Adjustment Program ................................................................ 118 About Adjustment Program .......................................................................... 118 How to set up the program ........................................................................... 118 Select the Model Name ................................................................................ 119 Market Destination Check ............................................................................ 120 Head Voltage ID Input ................................................................................. 121
26
CHAPTER
PRODUCT DESCRIPTION
EPSON Stylus COLOR 760
Revision C
1.1 FEATURES
The major features of EPSON color inkjet printer Stylus COLOR 760 are:
o High Color Print Quality n 1440 (H) X 720 (V) dpi printing n Four Color Printing (YMCK) n Traditional and New Microweave o Built-in Auto Sheet Feeder n Holds 100 cut-sheets (64g/m2) n Holds 10 envelopes n Holds 30 transparency films o Two Built-in Interfaces n Bi-directional parallel I/F (IEEE-1284 level 1 device) n USB o Windows/Macintosh exclusive
PRODUCT DESCRIPTION
FEATURES
9
EPSON Stylus COLOR 760
Revision C o Control Code n ESC/P Raster command n EPSON Remote command o Character Tables n Two international character sets:
- PC 437 (US, Standard Europe) - PC 850 (Multilingual)
1.2 SPECIFICATIONS
This section covers specifications of the printer.
1.2.1 Physical Specification
o Weight: o Dimension:
Storage: Printing: 450 mm (W) x 269 mm (D) x 175 mm (H) 450 mm (W) x 628 mm (D) x 303 mm (H) 6.0kg (excluding ink cartridges)
o Typeface n Bit map LQ font:
EPSON Courier 10 CPI
1.2.2 Printing Specification
o Print Method n On demand ink jet o Nozzle Configuration n Monochrome 144 nozzles (48 x 3 staggered) n Color 48 nozzles x 3 (Cyan, Magenta, Yellow) o Print Direction n Bi-direction with logic seeking o Print Speed & Printable Columns Table 1-1. Character Mode
Character Pitch 10 CPI (Pica) Printable Column 80 LQ Speed 238 CPS*
1.2.3 Paper Feeding
o Feed Method n Friction feed with ASF o Paper Path n Cut-sheet ASF (Top entry, Front out) o Feed Speed n 2.36 inch/sec (Normal, Continuous feed) n 4.5 inch/sec (Fast, Continues feed)
1.2.4 Input Data Buffer
n 256KB
*This value is the speed of normal-dot printing.
Table 1-2. Raster Graphics Mode
Horizontal Resolution 180 dpi 360 dpi 720 dpi Printable Area 8.26 inches 8.26 inches 8.26 inches Available Dot 1488 2976 5952 CR Speed 23.8/19 IPS 23.8/19 IPS 19 IPS
PRODUCT DESCRIPTION
SPECIFICATIONS
10
EPSON Stylus COLOR 760
Revision C
1.2.5 Electric Specification
[120V Version] Rated Voltage: Input Voltage Range: Rated Frequency Range: Input Frequency Range: Rated Current: Power Consumption: AC120V AC99132V 50 60Hz 49.5 60.5Hz 0.4A Approx. 18W (ISO10561 Letter Pattern) Approx. 3.5W in standby mode Energy Star compliant 10M ohms min. (between AC line and chassis, DC 500V) AC 1000V rms. 1 minutes or AC 1200V rms. 1 second (between AC line and chassis) AC220V240V AC198264V 5060Hz 49.560.5Hz 0.2 A Approx. 18W (ISO10561 Letter Pattern) Approx. 3.5W in standby mode Energy Star compliant 10M ohms min. (between AC line and chassis, DC 500V) AC 1500V rms. 1 minute (between AC line and chassis)
Insulation Resistance: Dielectric Strength:
[220 240V Version] Rated Voltage: Input Voltage Range: Rated Frequency Range: Input Frequency Range: Rated Current: Power Consumption:
Insulation Resistance: Dielectric Strength:
PRODUCT DESCRIPTION
SPECIFICATIONS
11
EPSON Stylus COLOR 760
Revision C
1.2.6 Environmental Condition
o Temperature n Operating: n Non-operating: o Humidity n Operating:
20 to 80% RH (without condensation / see the figure below for condition) 5 to 85% RH (without condensation / with shipment container) 10 to 35 °C (see the figure below for condition) -20 to 60 °C (with shipment container) 1 month at 40 °C and 120 hours at 60 °C
1.2.7 Reliability
Total Print Volume: Print Head Life: 75,000 pages (A4, Letter) 3 billion dots/nozzle
1.2.8 Safety Approvals
[120V Version] Safety Standards: EMI: [220240V Version] Safety Standards: UL1950 CSA22.2 No.950 FCC part 15 subpart B Class B CSA C108.8 Class B EN60950 (VDE) EN55022 (CISPR Pub.22) Class B AS/NZS 3548 Class B
n Non-operating: o Resistance to Shock n Operating: n Non-operating: o Resistance to Vibration n Operating: n Non-operating:
1G, within 1 ms 2G, within 2 ms (with shipment container)
EMI:
0.15G 0.50G (with shipment container)
1.2.9 Acoustic Noise
Level: Approx. 42dB(A)(According to ISO 7779) -Used media : Plain Paper - Print Quality: Fine
90 80 70 60
1.2.10 CE Marking
[220240V Version] Low Voltage Directive 73/23/EEC: EMC Directive 89/336/EEC: EN60950 EN55022 Class B EN61000-3-2 EN61000-3-3 EN50082-1 IEC801-2 IEC801-3 IEC801-4
Humidity (%)
50 40 30 20
10
20
27 30
35
40
Temperature (°C)
Figure 1-1. Temperature / Humidity of Range
PRODUCT DESCRIPTION
SPECIFICATIONS
12
EPSON Stylus COLOR 760
Revision C
1.3 INTERFACE
This printer provides USB and parallel interface as standard. DATA -STROBE tsetup BUSY tready -ACKNLG treply tack tnbusy tbusy tstb tnext
data byte n data byte n+1
thold
1.3.1 Parallel Interface (Forward Channel)
Transmission Mode: Synchronization: Handshaking: Signal Level: Adaptable Connector: 8 bit parallel, IEEE-1284 compatibility mode By STROBE pulse BY BUSY and ACKNLG signal TTL compatible level 57-30360 (amphenol) or equivalent
BUSY signal is set high before setting either -ERROR low or PE high, and held high until all these signals return to their inactive state. BUSY signal is at high level in the following cases:
Figure 1-2. Data Transmission Timing Table 1-3.
Parameter tsetup thold tstb tready Minimum 500ns 500ns 500ns 0 0 500ns 0 0 Maximum 500ns 120ns 200ns 10us -
n During data entry (see data transmission timing) n When input data buffer is full n During -INIT signal is at low level or during hardware initialization n During printer error (see -ERROR signal) n When the parallel interface is not selected
ERROR signal is at low level when the printer is in one of the following states:
n Printer hardware error (fatal error) n Paper-out error n Paper-jam error n Ink-out error
PE signal is at high level during paper-out error.
tbusy tt-out* tt-in** treply tack tnbusy tnext
* Rise and fall time of every output signal. ** Rise and fall time of every input signal. *** Typical timing for tack is shown on the following page.
PRODUCT DESCRIPTION
INTERFACE
13
EPSON Stylus COLOR 760
Revision C
Table 1-4. Typical Time of tack
Parallel I/F Mode High Speed Normal Speed Typical Time of tack 1us 3us 1 2 3 4 5 VOH = 2.4V VOL = 0.4V 6 7 8 9 10 Pin No.
Table 1-6. Connector Pin Assignment and Signals
Signal Name -STROBE DATA0 DATA1 DATA2 DATA3 DATA4 DATA5 DATA6 DATA7 -ACKNLG Return GND Pin 19 20 21 22 23 24 25 26 27 28 In/Out Functional Description The strobe pulse. Read-in of data is performed at the falling edge of this pulse.
In In In In In In In In In Out
Table 1-5. Signal Level: TTL Compatible (IEEE-1284 level 1 device)
Parameter VOH* VOL* IOH* IOL* CO VIH VIL IIH IIL CI Minimum -0.5V 0.8V Maximum 5.5V 0.32mA 12mA 50pF 2.0V 0.32mA 12mA 50pF VIH = 2.0V VIL = 0.8V Condition
The DATA0 through DATA7 signals represent data bits 0 to 7, respectively. Each signal is at high level when data is logical 1 and low level when data is logical 0.
This signal is a negative pulse indicating that the printer can accept data again. A high signal indicates that the printer cannot receive data. A high signal indicates paper-out error. Always at high level when the printer is powered on. Not used. The falling edge of a negative pulse or a low signal on this line causes the printer to initialize. Minimum 50us pulse is necessary. A low signal indicates printer error condition. Not used.
11 12 13 14
BUSY PE SLCT -AFXT
29 28 28 30
Out Out Out In
* A low logic level on the Logic H signal is 2.0V or less when the printer is powered off, and this signal is equal to or exceeding 3.0V when the printer is powered on. The receiver shall provide an impedance equivalent to 7.5K ohm to ground.
31
-INIT
30
In
32 36
-ERROR -SLIN
29 30
Out In
PRODUCT DESCRIPTION
INTERFACE
14
EPSON Stylus COLOR 760 Table 1-6. Connector Pin Assignment and Signals (continued)
Pin No. 18 35 17 16,33, 19-30 15,34 Signal Name Logic H +5V Chassis GND GND NC Return GND Pin In/Out Out Out Functional Description Pulled up to +5V via 3.9K ohm resistor. Pulled up to +5V via 3.3K ohm resistor. Chassis GND Signal GND Not connected
Revision C
NOTE: In/Out refers to the direction of signal flow from the printer's point of view.
PRODUCT DESCRIPTION
INTERFACE
15
EPSON Stylus COLOR 760
Revision C Table 1-7. Connector Pin Assignment and Signals (continued)
Pin No. 32 36 18 35 In/Out In In In In In In In In In Out Out Printer clock signal. Printer busy signal and reverse channel transfer data bit 3 or 7. Acknowledge data request signal and reverse channel transfer data bit 2 or 6. X-flag signal and reverse channel transfer data bit 1 or 5. Host busy signal. Not used. The DATA0 through DATA7 signals represent data bits 0 to 7, respectively. Each signal is at high level when data is logical 1 and low level when data is logical 0. These signals are used to transfer the 1284 extensibility request values to the printer. Functional Description Host clock signal. 17 16,33, 19-30 15,34 Chassis GND GND NC Signal Name -DataAvail / DataBit-0,4 1284-Active Logic-H +5V Return GND Pin 29 30 In/Out Out In Out Out Functional Description Data available signal and reverse channel transfer data bit 0 or 4. 1284 active signal. Pulled up to +5V via 3.9K ohm resistor. Pulled up to +5V via 3.3K ohm resistor. Chassis GND Signal GND Not connected
1.3.2 Parallel Interface (Reserve Channel)
Transmission Mode: Adaptable Connector Synchronization: Handshaking: Data Trans. Timing: Signal Level: IEEE-1284 nibble mode See forward channel. Refer to the IEEE-1284 specification Refer to the IEEE-1284 specification Refer to the IEEE-1284 specification IEEE-1284 level 1 device See forward channel.
Table 1-7. Connector Pin Assignment and Signals
Pin No. 1 2 3 4 5 6 7 8 9 10 11 Signal Name HostClk DATA0 DATA1 DATA2 DATA3 DATA4 DATA5 DATA6 DATA7 PtrClk PtrBusy / DataBit-3,7 AckDataReq / DataBit-2,6 Xflag / DataBit-1,5 HostBusy -INIT Return GND Pin 19 20 21 22 23 24 25 26 27 28 29
Note) In/Out refers to the direction of signal flow from the printer's point of view.
Extensibility Request: The printer responds affirmatively when the extensibility request values are 00H or 04H, which means, 00H: 04H: Request Nibble Mode Reverse Channel Transfer. Request Device ID; Return Data Using Nibble Mode Rev Channel Transfer.
12
28
Out
13 14 31
28 30 30
Out In In
PRODUCT DESCRIPTION
INTERFACE
16
EPSON Stylus COLOR 760
Device ID: The printer sends the following device ID string when it is requested. When IEEE1284.4 is enabled, [00H] [5AH] MFG: EPSON; CMD: ESCPL2, BDC, D4; MDL: Stylus[SP]COLOR[SP]760; CLS: PRINTER; DES: EPSON[SP]Stylus[SP]COLOR[SP]760; When IEEE1284.4 is disabled, [00H] [57H] MFG: EPSON; CMD: ESCPL2, BDC; MDL: Stylus[SP]COLOR[SP]760; CLS: PRINTER; DES: EPSON[SP]Stylus[SP]COLOR[SP]760;
Revision C
1.3.3 USB Interface
Based on: "Universal Serial Bus Specifications Rev. 1.0" "Universal Serial Bus Device Class Definition for Printing Devices Version 1.0" Bit Rate: 12Mbps (Full Speed Device) Data Encoding: NRZI Adaptable Connector: USB Series B Recommended Cable Length: 2 meters Standard:
Table 1-8. Connector Pin Assignment and Signals
Pin No. 1 2 3 4 Signal Name VCC -Data +Data Ground I/O Bi-D Bi-D Function Description Cable power. Max. power consumption is 2mA. Data Data, pull up to +3.3 V via 1.5K ohm resistor. Cable ground
NOTE 1:[00H] denotes a hexadecimal value of zero. NOTE 2:MDL value depends on the EEPROM setting. NOTE 3:CMD value depends on the IEEE1284.4 setting.
Pin #2
Pin #1
Pin #3
Pin #4
Figure 1-3. USB Pin Assignment
PRODUCT DESCRIPTION
INTERFACE
17
EPSON Stylus COLOR 760
Revision C o Automatic Selection
An initial state is compatible interface and starts IEEE1284.4 communication when magic strings (1284.4 synchronous commands) are received.
1.3.4 Preventing Data Transfer Time-out of Hosts
Generally, hosts abandon data transfer to peripherals when a peripheral is in the busy state for dozens of seconds continuously. To prevent this kind of timeout, the printer receives data very slowly, several bytes per minute, even if the printer is in the busy state. The slowdown starts when the remaining input buffer becomes several hundreds of bytes. Finally, the printer gets into the busy state continuously when the input buffer is full. USB and IEEE1284.4 on the parallel interface do not require this function.
o On
An initial state is IEEE1284.4 communication and data that received it by the time it is able to take synchronization by magic string (1284.4 synchronous commands) is discarded.
o Off
1.3.5 Interface Selection
The printer has two built-in interfaces: the USB and parallel interface. These interfaces are selected automatically.
An initial state is compatible interface and never starts IEEE1284.4 communication even if magic strings (1284.4 synchronous commands) are received.
o Automatic Selection
In this automatic interface selection mode, the printer is initialized to the idle state scanning which interface receives data when it is powered on. Then the interface that received data first is selected. When the host stops data transfer and the printer is in the stand-by state for seconds, the printer is returned to the idle state. As long as the host sends data or the printer interface is in the busy state, the selected interface is let as it is.
o Interface State and Interface Selection
When the parallel interface is not selected, the interface gets into the busy state. When the printer is initialized or returned to the idle state, the parallel interface gets into the ready state. Note that the interrupt signal such as the -INIT signal on the parallel interface is not effective while that interface is not selected.
1.3.6 IEEE1284.4 Protocol
The packet protocol described by IEEE1284.4 standard allows a device to carry on multiple exchanges or conversations which contain data and/or control information with another device at the same time across a single point-to-point link. The protocol is not, however, a device control language. It does provide basic transport-level flow control and multiplexing services. The multiplexed logical channels are independent of each other and blocking of one has no effect on the others. The protocol operates over IEEE1284.
PRODUCT DESCRIPTION
INTERFACE
18
EPSON Stylus COLOR 760
Revision C
1.4 OPERATOR CONTROLS
1.4.1 Operating Switch
Operating switch is located on the control panel.
1.4.2.2 Indicators
(1) Power Lights when the operating switch is "ON" and AC power is supplied. (2) Paper Out Lights during the paper-out condition, and blinks during the paper-jam condition. (3) Ink Out (Black) Lights during no black ink condition, and blinks during the black ink low condition. (4) Ink Out (Color) Lights during no color ink condition, and blinks during the color ink low condition.
1.4.2 Control Panel
1.4.2.1 Switches
There are two non-lock type push switches, one lock-type push switch, and four LED lights.
Load/Eject Cleaning Power
3
4
2
1
Figure 1-4. Control Panel
PRODUCT DESCRIPTION
OPERATOR CONTROLS
19
EPSON Stylus COLOR 760
Revision C
1.4.3 Panel Functions
Table 1-9. Panel Functions
Switch Load / Eject (Push for less than 2 sec.*) Load / Eject (Push for 2 sec.*) Cleaning (Push for 2 sec.*) Cleaning (Push for less than 2 sec.*) Function · Loads or ejects a paper. · When the carriage is on the ink cartridge replacement position, return the carriage to the capping position. · Starts the ink cartridge replacement sequence.** · Moves the carriage to the cartridge replacement position. · Starts cleaning of the printhead. · In the condition of "Ink Low", "Ink Out", or "No Ink Cartridge", starts the ink cartridge replacement sequence.** · When the carriage is on the ink cartridge replacement position, return the carriage to the capping position.
Table 1-10. Panel Function with Power On
Switch Load / Eject Cleaning Load/Eject + Cleaning Pressing with Power On Function · 1) Starts status printing. *1 · Changes code pages / Select IEEE1284.4 mode for parallel I/F. *2 · Enters the special settings mode. (Factory use only). *3
*1: One of the following actions is carried out according to the content of 1BH of EEPROM.
Content of 1BH of EEPROM, [bit7] [bit6] 00 11 01 10 Action Print firmware version, ink counter, selected code page and nozzle check pattern. Start hex-dump printing. Start self test printing.
* It is described in the user's manual that three seconds are required. **This function is not available in printing status.
*2: Not described in the user's manual. *3: See the table below.
Table 1-11. Special Setting Mode
Switch Load / Eject Function · Initialize EEPROM and reset timer IC.
· Reset the ink overflow counter in EEPROM. Cleaning (Push for 10 seconds)
PRODUCT DESCRIPTION
OPERATOR CONTROLS
20
EPSON Stylus COLOR 760
Revision C
1.4.4 Printer Condition and Panel Status
Table 1-12. Printer Condition and LED Status
Indicators Printer Status Power Power On Condition Ink Sequence Ink Cartridge Replacement Mode Data Processing Paper Out Paper Jam Condition No Ink Cartridge / Ink End (Black) Ink Level Low (Black) No Ink Cartridge or Ink End (Color) Ink Level Low (Color) Enter EEPROM and Timer IC Reset Maintenance Request Fatal Error On Blink Blink Blink Blink Blink Ink Out (Black) Off On Blink Ink Out (Color) Off On Blink ON (for 1 second only) Blink On Blink On Blink Blink Priority Paper Out On Blink 9 6 5 8 4 3 7 7 7 7 2 1
1.4.5 Printer Initialization
There are three kinds of initialization methods, and the following explains each initialization. 1. Power-on Initialization This printer is initialized when turning the printer power on, or printer recognized the cold-reset command (remote RS command). When printer is initialized, the following actions are performed: (a) Initializes printer mechanism. (b) Clears input data buffer. (c) Clears print buffer. (d) Sets default values. 2. Operator Initialization This printer is initialized when turning the printer power on again within 10 seconds from last power off, or printer recognized the -INIT signal (negative pulse) of parallel interface. When printer is initialized, the following actions are performed: (a) Cap the printer head. (b) Eject a paper. (c) Clears input data buffer. (d) Clears print buffer. (e) Sets default values. 3. Software Initialization The ESC@ command also initialize the printer. When printer is initialized, the following actions are performed: (a) Clears print buffer. (b) Sets default values.
PRODUCT DESCRIPTION
OPERATOR CONTROLS
21
EPSON Stylus COLOR 760
Revision C
1.4.6 Errors
o Ink Out
When the printer runs out most of the ink of any color, it warns ink-low and keeps printing. When the printer runs out the whole ink of any color, it stops printing and indicates ink-out error. User is requested to install a new ink-cartridge in this state. An ink-cartridge that has been taken out once should never be used again. Re-installation of the cartridge not filled fully upsets the ink level detection and may cause a serious problem in the print head as a result.
o Paper Out
When the printer fails to load a sheet, it goes into a paper out error.
o Paper Jam
When the printer fails to eject a sheet, it goes into a paper jam error.
o No Ink-Cartridge
When the printer detects that ink-cartridge comes off, it goes into this error mode.
o Maintenance Request
When the total amount of ink wasted through the cleanings and flushing reaches to the limit, printer indicates this error and stops. The absorber in the printer enclosure needs to be replaced with new one by service personnel.
o Fatal Errors
Carriage control error or CG access error.
PRODUCT DESCRIPTION
OPERATOR CONTROLS
22
EPSON Stylus COLOR 760
Revision C
[Thickness]
1.5 PAPER
1.5.1 Paper Handling
Do not perform reverse feed more than 9.5mm (0.38").
0.075mm (0.003") - 0.085mm (0.0033")
*Transparency printing is available only at normal temperature.
1.5.2.3 Envelope
[Size]
1.5.2 Paper Specification
1.5.2.1 Cut Sheet
[Size] A4: Letter: B5: Legal: Statement: Executive: Photo Paper: [Thickness] 0.08mm (0.003") - 0.11mm (0.004") [Weight] 64g/m2 (17Ib.) - 90g/m2 (24Ib.) [Quality] Exclusive paper, Bond paper, PPC Width 210mm (8.3") x Length 297mm (11.7") Width 216mm (8.5") x Length 279mm (11.0") Width 182mm (7.2") x Length 257mm (10.1") Width 216mm (8.5") x Length 356mm (14.0") Width 139.7mm (5.5") x Length 215.9mm (8.5") Width 184.2mm (7.25") x Length 266.7mm (10.5") Width 101.6mm (4") x Length 152.4mm (6")
No.10: DL: C6:
[Thickness]
Width 241mm (9 1/2") x Length 104.8mm (4 1/8") Width 220mm (8.7") x Length 110mm (4.3") Width 162mm (6.4") x Length 114mm (4.5")
0.16mm (0.006") - 0.52mm (0.02")
[Weight]
45g/m2 (12Ib.) - 75g/m2 (20Ib.)
[Quality]
Bond paper, Plain paper, Air mail
*Envelope printing is available only at normal temperature. *Keep the longer side of the envelope horizontally at setting.
1.5.2.4 Index Card
[Size]
1.5.2.2 Transparency, Glossy Paper
[Size]
A4: Letter:
Width 210mm (8.3") x Length 297mm (11.7") Width 216mm (8.5") x Length 279mm (11.0")
A6 Index Card: A5 Index Card: 5 x 8" Index Card: 10 x 8" Index Card:
[Thickness]
Width 105mm (4.1") x Length 148mm (5.8") Width 148mm (5.8") x Length 210mm (8.3") Width 127mm (5.0" x Length 203mm (8.0") Width 127mm (5.0") x Length 203mm (8.0")
Less than 0.23mm (0.0091")
PRODUCT DESCRIPTION
PAPER
23
EPSON Stylus COLOR 760
Revision C
1.5.3 Printing Area
1.5.3.1 Cut Sheet
See the figure below and tables on the right for printable areas for Raster Graphics mode and Character mode. PW LM RM
Paper Size A4 Letter B5 Legal
Table 1-13. Character Mode
Left Margin (min.) 3mm (0.12") 3mm (0.12") 3mm (0.12") 3mm (0.12") Right Margin (min.) 3mm (0.12") 9mm (0.35") 3 m (0.12") 9mm (0.35") 3mm (0.12") 3mm (0.12") Top Margin (min.) 3mm (0.12") 3mm (0.12") 3mm (0.12") 3mm (0.12") 3mm (0.12") 3mm (0.12") Bottom Margin (min.) 14mm (0.54") /3mm (0.12")* 14 mm (0.54") / 3mm (0.12")* 14 mm (0.54") / 3mm (0.12")* 14 mm (0.54") / 3mm (0.12")* 14 mm (0.54") / 3mm (0.12")* 14 mm (0.54") / 3mm (0.12")*
TM
Statement 3mm (0.12") Executive 3mm (0.12")
NOTE: Refer to 1.5.2 Paper Specification for PW (paper width) and PL (paper length).
Printable Area
PL
Paper Size A4 Letter B5
Table 1-14. Raster Graphics Mode
Left Margin (min.) 3 mm (0.12") 3 mm (0.12") 3 mm (0.12") 3 mm (0.12") Right Margin (min.) 3 mm (0.12") 3 mm (0.12") 3 mm (0.12") 3 mm (0.12") 3 mm (0.12") 3 mm (0.12") Top Margin (min.) 3 mm (0.12") 3 mm (0.12") 3 mm (0.12") 3 mm (0.12") 3 mm (0.12") 3 mm (0.12") Bottom Margin (min.) 14 mm (0.54") / 3mm (0.12")* 14 mm (0.54") / 3mm (0.12")* 14 mm (0.54") / 3mm (0.12")* 14 mm (0.54") / 3mm (0.12")* 14 mm (0.54") / 3mm (0.12")* 14 mm (0.54") / 3mm (0.12")*
BM
Legal
Statement 3 mm (0.12")
Figure 1-5. Printable Area for Cut Sheet
Exclusive
3 mm (0.12")
* Bottom margin is reduced to 3mm when paper dimension is defined by using the command. However, print in the extra printable area may scramble. Note the bottom margin remains 14 mm without the command.
PRODUCT DESCRIPTION
PAPER
24
EPSON Stylus COLOR 760
Revision C
1.5.3.2 Envelopes
LM RM
TM
Printable Area
BM
Figure 1-6. Printable Area for Envelopes Table 1-15. Envelope Margin
Size #10 DL C6 Left Margin (min.) 3 mm (0.12") 3 mm (0.12") 3 mm (0.12") Right Margin (min.) 28 mm (1.10") 7 mm (0.28") 3 mm (0.12") Top Margin (min.) 3 mm (0.12") 3 mm (0.12") 3 mm (0.12") Bottom Margin (min.) 14 mm (0.55") 14 mm (0.55") 14 mm (0.55")
PRODUCT DESCRIPTION
PAPER
25
EPSON Stylus COLOR 760
Revision C
1.6 INK CARTRIDGE
1.6.1 Black Ink Cartridge
Type: Color: Print Capacity: Ink Life: Storage Temperature: Storage: Packing: Transit: Dimension: Exclusive Cartridge Black 900 pages/A4 (ISO/IEC 10561 Letter Pattern at 360 dpi) 2 years from date of production -20 oC to 40 oC (within a month at 40 oC) -30 oC to 40 oC (within a month at 40 oC) -30 oC to 60 oC (within 120 hours at 60 oC and within a month at 40 oC) 27.8 mm (W) x 52.7 mm (D) x 38.5 mm (H)
27.8
1.6.2 Color Ink Cartridge
Type: Color: Print Capacity: Ink Life: Storage Temperature: Storage: Packing: Transit: Dimension: Exclusive Cartridge Magenta, Cyan, Yellow 300 pages / A4 (360 dpi, 5% duty each color) 2 years from date of production -20 oC to 40 oC (within a month at 40 oC) -30 oC to 40 oC (within a month at 40 oC) -30 oC to 60 oC (within 120 hours at 60 oC and within a month at 40 oC) 42.9 mm (W) x 52.7 mm (D) x 38.5 mm (H)
43.2
52.7
52.7
51.2
42.9
38.5
38.5
41.4
Figure 1-8. Color Ink Cartridge
26.3
Note 1: Ink cartridge can not be re-filled. It is prepared only for an article of consumption. Note 2: Do not use the ink cartridge which contains life-expired ink. Note 3: Ink will be frozen under -4°C environment; however, it will be usable after placing it at room temperature for more than three hours.
Figure 1-7. Black Ink Cartridge
PRODUCT DESCRIPTION
INK CARTRIDGE
51.2
26
CHAPTER
OPERATING PRINCIPLES
EPSON Stylus COLOR 760
Revision C
2.1 Overview
This section describes the operating principles of the printer mechanism and electrical circuit boards. The EPSON Stylus COLOR 760 has the following boards: The basic structure of the printer mechanism is mostly common to the Stylus COLOR 400/600/440/640/740, except that the Stylus COLOR 760 uses a DC motor. Figure 2-1 shows the printer mechanism block diagram for the Stylus COLOR 760.
Intermittent Gear PF Motor Pinion Loop Scale PF Drive Gear (high precision) ASF Sensor
o Main board: o Power supply board: o Panel board:
C298MAIN Board C298PSB/PSE Board C298PNL Board
2.1.1 Printer Mechanism
Unlike other EPSON ink jet printers, the Stylus COLOR 760 uses DC motor for power source. Use of the DC motor enable the printer to lower noise during printing to a great extent. Table 2-1 shows the various motor types used in the printer and their applications.
PF Motor Flashing Window (80th column) Star Wheel roller Detector Wheel
Loading Shaft Photo Interrupter (Encoder)
Table 2-1. Motor Types and Corresponding Applications
Motor Name CR Motor Type DC with brush Application / Feature Used to drive the carriage making little noise. A a linear scale is used to monitor the motor's operating condition. · Drives paper feeding rollers used to send paper at specified speeds and load/eject paper. · Drive the ASF used to send paper to PF roller. · Drive CR Lock lever When the CR unit is in the home position, the CR lock lever is fixed the CR unit. · Drive Pump Unit to absorb the ink To monitor paper feeding pitch, a loop scale is attached beside the high-precision gear.
Bk I/C Sensor CMY I/C Sensor Carriage Unit Printhead (one unit) Timing Belt Cap Unit (without a valve)
Loading Rollers
PE Sensor
PF Motor
DC with brush
Liner Scale
Pump Unit CR Guide Shaft PF Roller CR Motor (DC motor) PG Lever
Figure 2-1. Printer Mechanism Block Diagram
Operating Principles
Overview
28
EPSON Stylus COLOR 760
Revision C
2.1.1.1 Printing Mechanism
The basic operating principles of the printhead, which plays a major role in printing, are the same as previous models; ones that use a on-demand type UCHIP head method. (Refer to Figure1-1.) Also, unlike the Stylus Color IIs, 820 and 200, the Stylus COLOR 760 is not an automatic correction type. So, in order to correct dispersion of multi layer piezo electric element that drives each nozzle, you are required to input a VH value written on the top surface of the printhead by using an exclusive program when you replace the printhead, control board, or printer mechanism. (Note there are no resistor arrays to determine the VH voltage on the main control board.) Following explains printhead.
I/C Sensor Actuator
Nozzle Selector Board
Ink Cartridge Needle
o PZT
PZT is an abbreviation of Piezo Electric Element. Print signals from the Main board are sent through the driver board on the printhead unit to the PZT. Then, the PZT pushes the top cavity which has ink stored to discharge the ink from each nozzle on the nozzle plate.
Filter
o Cavity Set
The ink absorbed from the ink cartridge goes through the filter and then is stored temporarily in this tank called "cavity" until PZT is driven.
Nozzle Plate PZT Cavity
o Nozzle Plate
The board with nozzle holes on the printhead surface is called Nozzle Plate.
Figure 2-2. Printing Mechanism
o Filter
When the ink cartridge is installed, if any dirt or dust around the cartridge needle is absorbed into the head, there is a great possibility of causing nozzle clog and disturbance of ink flow, and finally causing alignment failure and dot missing. To prevent this problem, a filter is set below the cartridge needle, where ink is filtered.
Operating Principles
Overview
29
EPSON Stylus COLOR 760
Revision C
2.1.1.2 Printing Process
Figure 2-3 and Figure 2-4 show the normal state and ejecting state of the printhead, respectively. 1. Normal State: When the print signal is not output, PTZ also does not move from a waiting state (normal state). (Refer to Figure 2-3.) 2) Ejecting State: When the print signal is output from the C298MAIN board, IC (IR4C463S: Nozzle Selector) located on the printhead unit latches data once by 1-byte unit. An appropriate PZT latched by the nozzle selector is pushed into the cavity by the common voltage applied from the main board. By this operation, ink stored in the cavity spurts out from nozzles. (Refer to Figure 2-4.) Ink Course PZT Cavity
Nozzle
Nozzle Plate
Figure 2-3. Print Head Normal State
Figure 2-4. Print Head Ejecting State
Operating Principles
Overview
30
EPSON Stylus COLOR 760
Revision C
The printhead, a core of the printing mechanism, is stored in the carriage unit. When the adjustment lever is moved up and down, this printhead is maintained tilt in a flexible and adjustable structure by the tilt adjustment mechanism. Also, the parallelism adjustment levers, mounted on the left and right sides of the carriage guide shaft, are used to set the carriage guide shaft parallel to the platen when the shaft has been installed to the printer mechanism. After this adjustment is completed, moving the PG adjustment lever sets the distance between the platen surface and the printhead surface to one of two possibilities: 1.14 mm or 1.84mm. You can change the distance by rotating the shafts of the carriage guide shaft which itself is decentralized, with the operation of PG lever. This is the mechanism that the user can use to adjust the appropriate PG value according to the printing result or any other environmental conditions such as paper thickness.
2.1.1.3 Carriage Mechanism
The carriage mechanism for the Stylus COLOR 760 is mostly the same as for other ink jet printers except it is driven by a DC motor. See the table below for the carriage motor specifications.
Table 2-2. Carriage Motor Specification
Items Type Drive Voltage DC Motor with brush +42 V +/- 5%(DRV IC voltage) Specifications
Internal Resistance 29.2 ohms +/- 25% Inductance Drive Method Driver IC 30.8 mH +/- 25% Constant Current Chopping LB1947
Unlike a stepping motor, the DC motor that drives the carriage can not detect the current carriage position by referring to the pulses given. Therefore, a linear scale is attached along the carriage operation range to enable the printer to mechanically detect the carriage position. (Same as the Stylus COLOR 900) The linear scale is also used to produce the print timing signal (PTS signal), to which the printer refers to for a correct ink ejection timing. For detailed information on the CR motor control circuit, see Section 2.2.
Timing Belt PF Roller CR motor
Liner Scale for
CR unit
.
Figure 2-5. Carriage Mechanism (Top view)
Operating Principles
Overview
31
EPSON Stylus COLOR 760
Revision C
2.1.1.4 Platen Gap (PG) Adjust Mechanism
The PG adjustment, at the right of the printer mechanism, consists of the PG lever, PG support lever, right/left parallelism adjustment levers, and CR guide shaft. The PG adjustment mechanism is designed to keep the platen gap correct for the paper thickness to prevent ink from smearing. The PG support lever joins the CR guide shaft, which has and eccentricity via PG support lever. Switching the lever from "0" to "+" rotates the CR shaft and changes the platen gap from narrow to wide.
2.1.1.5 Paper Feeding Mechanism
The paper feeding mechanism transports paper loaded from ASF using the PF rollers and paper eject rollers. A new type of DC motor is used for the PF motor. See the table below for the DC motor specifications.
Table 2-4. PF Motor Specifications
Item Motor type Drive voltage Description DC Motor with Brush +42V +/- 5% (DRV IC voltage) 31.1 ohm +/- 25% 26.6mH +/- 25% A3958
Table 2-3. Platen Gap Adjust Lever Setting
Paper All Media If you find any print problems or you use thick paper Lever Position Front PG adjustment value 0 mm (1.14mm between head and platen) 0.7mm (1.84mm between head and platen)
Coil Resistance Drive frequency [Hz] Control method
Rear
Unlike a stepping motor, the DC motor that drives the paper feeding mechanism can not measure the paper feeding amount by referring to the pulses given. For this reason, the loop scale and encoder sensor are directly attached to the left end of the PF roller shaft to mechanically control paper feed amount. See Section 2.2 for detailed information on the PF motor control circuit. Drive from the PF motor is sent to the PF rollers and paper eject rollers as described below.
o To the PF rollers:
PF motor pinion gear (CCW rotation) Spur gear (76) PF rollers
o To the eject rollers:
PF motor pinion gear (CCW rotation) Spur gear (76) Combination gear (13.5, 308) Spur gear (28) Paper eject rollers
NOTE: Above CCW rotation is mentioned viewing from the PF motor pinion gear side.
Figure 2-6 in the next page gives the paper feeding mechanism block diagram, showing the parts along the PF motor drive transmission paths.
Operating Principles
Overview
32
EPSON Stylus COLOR 760
Revision C
Loop Scale
PF Roller
Spur Gear 76
[Previous Models]
Paper
Printhead Star Wheel Assy.
Support Roller
Spur Gear 28 Paper Eject Roller Combination Gear13.5,30.8 PF motor Star Wheel Assy. PF Roller
Bottom margin 3 mm touches the printhead surface.
Eject Roller Platen
Figure 2-6. Paper Feeding Mechanism (Top View)
The printer loads paper at the ASF, which is detected by the PE sensor attached to the right side of the top frame, and advances it to send the paper's leading edge to the halfway of the front paper guide. Then, to correct deflection, the printer feeds the paper back specified steps toward ASF, and advances the paper again toward the front paper guide and stops it at the specified TOF (Top Of Form) position. Once the printer starts printing, it transports paper using the PF rollers and sub rollers, and as the printer transports or printing on the tailing 14 mm, it uses a star wheel gear and paper eject rollers. Like the Stylus COLOR 440/640/740, this printer also provides this extra printable range of 14 mm from the bottom edge, excluding the bottom margin of 3mm, by changing the position of the star wheel gear; it has been shifted by 5° from the top of the eject roller toward the front paper guide. Due to this change, the tailing edge of paper is suppressed, and the printer can advance paper steadily when printing around the bottom area. See Figure 2-7 next page that shows how paper is transported and parts involved.
[Stylus COLOR 760]
Five Degrees
Steady
Figure 2-7. Paper Transportation (Right side view)
Operating Principles
Overview
33
EPSON Stylus COLOR 760
Revision C
If the carriage is left uncapped for a long time, ink on its surface will become gradually thick and not spurt from the nozzles as a result. To make matters worse, the holes (crater) of the nozzles may be completely clogged by the thick ink, and they may not be able to return to a normal condition just by a cleaning operation. To prevent this, the printer enters a carriage lock condition in the following conditions.
2.1.1.6 CR Lock Mechanism
The carriage lock mechanism prevents the carriage from being left at an uncapped position for a long time, that is usually caused by vibration during printer transportation, user's mishandling of the printer, and so on. The CR Lock mechanism is driven with the DC PF motor. As for the motor specifications, refer to Table 2-4. The PF motor drive is used for the Paper Feed Mechanism also and the CR lock mechanism is controlled depending on the direction of the PF motor rotation. The CR lock mechanism is assembled on the right tip of the Paper Eject Roller as shown in the following figure.
o After Power-off operation:
If the printer power is turned off in the middle of printing or any other performances, carriage lock takes place in the end after an initialization operation.
o After Power-on operation:
After the printer power is turned on and an automatic power-on cleaning is completed, carriage lock is performed. The power-on cleaning is an automatic head cleaning that runs when the printer power is turned on. The timer IC always calculates printer's power off time using power from a lithium battery mounted on the C298MAIN board. The power-on cleaning function automatically selects a correct cleaning level according to the length of time which the printer has been turned off.
Top view
Pump Planetary Lever
Right side view
CR Unit Bushing 6 CR Lock lever
o After ejecting paper:
After the Load/Eject button is pressed and the paper is ejected, if the printer does not receive any data, it performs carriage lock and goes to a standby state. However, if paper is loaded by pressing the Load/Eject button, the printer does not perform the carriage lock operation. PF motor torque is always transmitted to the CR lock lever side, but the operation of the CR lock mechanism varies depending on the rotational direction of the PF motor, as shown in the following below.
Paper Eject Roller Middle Frame
Pump Planetary Lever Fixing Guide
Figure 2-8. CR Lock mechanism
While the PF motor drive is used for paper feeding (PF motor rotation: CCW), the CR Lock lever is set under the Paper Eject Frame. But the CR Lock lever rises up with the CW rotation of the PF motor and locks the CR unit. Drive from the PF motor is sent to the CR Lock lever via Paper Eject Roller below.
Table 2-5. CR Lock mechanism & PF motor rotational direction
Directions Counterclockwise Clockwise Corresponding Functions · Releases the CR lock lever. · Sets the CR lock lever.
o To the CR lock lever
PF motor pinion gear (CW rotation) Spur gear (76) Combination gear (13.5, 30.8) Spur gear (28) Paper eject rollers CR lock lever.
Operating Principles
Overview
34
EPSON Stylus COLOR 760
Revision C
2.1.1.7 Paper Loading Mechanism
The paper loading mechanism loads paper at the ASF unit and feeds paper to the PF rollers. The ASF unit, the same as in the Stylus COLOR 440/640/740, uses a DC PF motor. Drive sent from this motor is switched between the ASF unit side and Pump/PF roller side by the disengage mechanism. Drive from the PF motor is transmitted to the ASF as described below: When the PF motor torque is switched to the ASF unit side by the disengage mechanism, the function of the ASF mechanism varies depending on the rotational direction of the PF motor, as shown in the table below.
o Drive transmission to the ASF unit
1) When the CR unit moves to the left end of the CR shaft, the DE lever is pushed to the left end and the Spur gear 26.4 meshes with the Combination gear (16,40.8). 2) Drive of the PF motor is sent to the ASF side. 3) Drive from the PF motor is transmitted as described below. PF Motor pinion gear Spur gear (76) Spur gear (26.4) Combination gear (16,40.8) Spur gear (23.2) Spur gear (27.2) in ASF Figure 2-9 shows the disengage mechanism and the parts involved.
Table 2-6. ASF unit function & PF Motor rotational direction
Directions Counterclockwise Clockwise Corresponding Functions · Picks up paper · Resets paper to the correct paper set position using the Return Lever.
Spur Gear 27.2 Spur Gear 23.2 Combination Gear 16,40.8 Spur Gear 76 Spur Gear 26.4
PF Roller DE lever
Figure 2-9. Disengage Mechanism (Top view)
Operating Principles
Overview
35
EPSON Stylus COLOR 760
Revision C
Torque sent from the PF motor to the ASF unit via the disengage mechanism is used for the following operation.
o Paper loading operation
Like the Stylus COLOR 440/640/740, ASF of this printer has the multiple paper loading prevention mechanism to provide steady paper loading. This mechanism prevents a sheet of paper from falling from the paper set position into the paper path. A paper return lever in the mechanism pushes paper that may have fallen off back onto the hopper. After this motion is completed, the LD roller starts loading paper. The paper loading mechanism, including the multiple paper loading prevention mechanism, is described in the following steps.
1. When the printer power is turned on, the PFmotor rotates counterclockwise to detect ASF home position. Then the motor rotates clockwise specified steps to set the LD roller and paper turn lever in place. (See "Standby State" in Figure 2-10.) 2. When the paper loading signal is sent from the PC and the Load/Eject button is pressed, PF motor turns counterclockwise to let the LD roller load paper. (See "Paper Pick Up State" in Figure 2-10.) 3. When the paper is transported to the PF roller, the LD roller stops where it loses friction. (See "PF Roller Paper Feed State" in Figure 2-10.) 4. When the next print signal is sent or Load/Eject button is pressed, the PF motor rotates clockwise specified steps to set the LD roller and the paper return lever in place. (See "Standby State" in Figure 2-10.)
NOTE: If no print signal is sent for several seconds in step 4, the LD roller and the paper return lever automatically return to the standby state.
LD Roller
Hopper Cam
Hopper Spring
2 3
Pinch Roller
Paper Return Lever
Pad
Pad Spring
[Stand-by State]
[Paper Pickup State]
[PF Roller Paper Load State]
Figure 2-10. Multiple Paper Loading Prevention Mechanism (right side view)
Operating Principles
Overview
36
EPSON Stylus COLOR 760
Revision C
2.1.1.8 Pump Mechanism
The pump mechanism absorbs ink from the printhead or the cap assembly. The wiper for head cleaning is attached in the cap assembly. The pump mechanism is driven by the DC PF motor. Drive sent from this motor is switched between CR lock lever mechanism (PF roller & Paper Eject Roller) side and Pump unit side by the Pump disengage mechanism. See Table 2-4 for the PF motor specifications. Torque from the PF motor is sent to the pump unit by the switching operation of the planetary gear in the Pump disengage mechanism. The PF motor torque is transmitted to the pump mechanism as described below.
Figure 2-11 show you the pump disengagement mechanism.
Top view
Middle Frame CR lock Lever Pump planetary lever Pump planetary lever fixing guide Tension spring
Right side view
o Torque transmission to the pump unit
1)When the CR unit moves to capping position, the protusion of the CR unit pushes the Pump planetary lever fixing guide to the right side and release the Pump planetary lever. (Pump planetary lever is fixed with the Pump planetary lever fixing guide to the CR lock lever mechanism side.) 2)The PF motor rotates to counterclockwise direction and the Paper eject roller rotates to paper eject direction. The Pump planetary lever also rotates about 90 degree angle to the Pump mechanism side. 3)Torque from the PF motor is transmitted as described below. PF motor pinion gear (CCW rotation) Spur gear (76) Combination gear (13.5, 30.8) Spur gear (28) Paper eject rollers Pump planetary lever Spur Gear 10.4 (Pump DE unit) Spur Gear 8.4 (Pump DE unit) Combination Gear 12, 28.8. Pump unit. Figure 2-11 shows you torque transmission to the Pump unit.
Spur Gear 76 Combination Gear 13.5, 30.8 Paper Eject Roller Pump disengage mechanism
Spur Gear 10.4 Spur Gear 8.4 CR lock lever is set under the Paper Eject roller Frame. Combination Gear 12, 28.8
Printhead pushes the Planetary lever fixing guide to the right side and releases the Pump planetary lever. The Pump planetary lever rotates 90 degree angl and the Spur gear 8.4 engages with the Combination gear12, 28.8.
PF Motor Spur gear 28 CR Lock lever Pump Unit
Figure 2-11. Torque transmission to Pump Unit (Top view)
Figure 2-12. Pump disengagement mechanism
Operating Principles
Overview
37
EPSON Stylus COLOR 760
When the PF motor torque is switched to the pump unit side by the disengage mechanism, the function of the pump mechanism varies depending on the rotational direction of the motor, as shown in the table below.
Revision C
Table 2-7. Pump unit Functions & PF motor rotational direction
Directions Counterclockwise Clockwise Corresponding Functions · Ink absorption by the pump · Sets the wiper. · Releases the pump. · Resets the wiper.
Figure 2-13 shows the operating principles of the pump mechanism.
Counterclockwise
Clockwis
Tube pressured
Tube released
Figure 2-13. Pump Mechanism
Operating Principles
Overview
38
EPSON Stylus COLOR 760
Revision C
2.1.1.9 Capping Mechanism
The capping mechanism, which is driven by the pump unit, caps the printhead closely to maintain air tightness of the cap. This operation is required to vacuum ink from the ink cartridges, printhead, cavity, and cap. Also, to moisten the inside of the cap while the printer power is off, this mechanism works to keep the cap and the printhead surface in a tight contact. This function prevents ink from clogging while the printer is not in use. For a specific feature of the Stylus COLOR 760, it has a newly designed valveless capping mechanism instead of other printers' capping mechanism that integrates an air valve. An air valve is usually equipped to remove bubbles created inside the cap by releasing the negative pressure. However, due to change in the ink sequence, the new valveless capping mechanism enables this printer to maintain the initial ink charge and cleaning effects at the same level as before. Figure 2-14 outlines the valveless capping mechanism.
SC440/640/740 models
Flag for Carriage
SC 760 model
Flag for Carriage
Negative pressure
Ink Eject Valve Ink Eject Valve Negative pressure Valve
Closed state
Released state
Flags for Frame Air valve is not assembled in this portion.
Figure 2-14. Valveless Capping Mechanism
Operating Principles
Overview
39
EPSON Stylus COLOR 760
Revision C
2.2 Electrical Circuit Operating Principles
The electric circuit of the Stylus COLOR 760 is composed of the following boards.
o Main board: o Power supply board: o Panel board:
C298MAIN Boar