User manual OKI DATA MICROLINE 380 - SERVICE MANUAL

Page: 1 Service Guide ML380 Chapter 0 About This Manual ML380 Dot Matrix Printer Adobe Acrobat printable reference copy of the OKIDATA Service Training Manual. 09/17/97 Note: This Adobe Acrobat version of the Okidata Service Training Manual was built with the pictures rendered at 300 dpi, which is ideal for printing, but does not view on most displays well. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Table of Contents Page Service Guide ML380 0 About This Manual Front Cover Manual Copyright 1 Product Specifications 1.1 Overview 1.2 Physical Specifications 1.3 Power Requirements 1.4 Environmental Conditions 1.5 Agency Approvals 1.6 Operational Specifications 1.7 Paper Specifications 1.8 Memory Specifications 1.9 Consumables 1.10 Options 1.11 Reliability 2 Principles of Operation 2.1 Principles of Operation - General Information ....2.1.02 Microprocessor and Peripheral Circuits ....2.1.03 Initialization ....2.1.04 Interface Control ....2.1.05 Printhead Drive Circuit ....2.1.06 Spacing Drive Circuit ....2.1.07 Line Feed Circuit ....2.1.08 Alarm Circuits ....2.1.09 Paper End Detection Circuit ....2.1.10 Power Supply 2.2 Mechanical Operation - Printhead Mechanism ....2.2.02 Spacing ....2.2.03 Ribbon Drive ....2.2.04 Paper Feed ....2.2.05 Paper-End Detection ....2.2.06 Semi-Automatic Sheet Feeder (SASF) ....2.2.07 Paper Park 3 Maintenance & Disassembly 3.1 Maintenance - General Information ....3.1.02 Maintenance Tools ....3.1.03 Maintenance Precautions 3.2 Disassembly/Assembly Procedures - General Information ....3.2.01 Paper Separator ....3.2.02 Printhead ....3.2.03 Upper Cover Assembly ....3.2.04 Space Rack 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 Table of Contents ....3.2.05 Ribbon Feed Gear Assembly ....3.2.06 Mini-Pitch (Space) Belt ....3.2.07 Head Connector Assembly ....3.2.08 Main Control Board (UMMB) ....3.2.09 Operation Panel ....3.2.10 Line Feed Motor ....3.2.11 Photosensor Assembly (Paper End) ....3.2.12 Bail Arms ....3.2.13 Carriage Frame ....3.2.14 Platen Assembly ....3.2.15 Pressure Roller Assembly ....3.2.16 Paper Pressure Guide ....3.2.17 Tractor Assembly ....3.2.18 Microswitch Assembly (SASF) ....3.2.19 Microswitch Assembly (Home Position Switch) ....3.2.20 Printer Mechanism ....3.2.21 Power Supply Unit ....3.2.22 Space Motor Assembly ....3.2.23 Bottom Paper Guide Lever 3.3 Printer Adjustments ....3.3.02 Gap Between Platen and Printhead ....3.3.03 Space Belt Tension ....3.3.04 Key Combinations ....3.3.05 Menu Operation / Menu Select Mode - General Information ........From Print Mode ........From Power-OFF ........Printing the Menu ........Sample Menu ........Reset Menu to Factory Defaults ........Limited Operation ........Menu Settings ....3.3.06 Top of Form ....3.3.07 Paper Park ....3.3.08 Paper Tear Off ....3.3.09 Resets 3.4 Cleaning 3.5 Lubrication 3.6 Shipping Instructions 4 Failure & Repair Analysis 4.1 Failure & Repair Analysis - Introduction ....4.1.02 Printer Serial Number Identification ....4.1.03 Firmware Revision Identification 4.2 Reporting Problems - General Information Page 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 Table of Contents ....4.2.02 Problem Lists ....4.2.03 Reporting Methods 4.3 Troubleshooting Updates General Information 4.4 Troubleshooting Tips ....4.4.02 Problem Categories ....4.4.03 START HERE Flowchart ....4.4.04 Tips for Preventing Image Problems ....4.4.05 Common Problems 4.5 Abnormal Output 4.6 Fault Alarms - General Information ....4.6.02 Fault Alarm Lamp Display 4.7 Repair Analysis Procedures (RAPS) - Using The RAPS ....4.7.02 RAP Index ........RAP 01: No Power ........RAP 02: Space Operation Does Not Operate Normally ........RAP 03: Wrong Character or Missing Dots ........RAP 04: Line Feed Trouble ........RAP 05: Data Receiving Failure 4.8 Printer Tests - General Information ....4.8.02 Rolling ASCII Test ....4.8.03 Font Test ....4.8.04 Serial Interface Loopback Test - General Information ........Loopback Connector Configuration Diagram ........Procedure ........Serial Cable Information ........Serial Interface Signal Requirements ........Commonly Used Serial Cable Configurations ....4.8.05 Hexadecimal Dump Mode 4.9 Resistance Checks - General Information ....4.9.02 Main Control Board (UMMB) Voltage Check Points ....4.9.03 Connectors Block Diagram ....4.9.04 Connector Location ....4.9.05 Resistance Diagrams - Printhead ........Space and Line Feed Motors ....4.9.06 Head Cable Connection A Board Diagrams A1 Board Diagrams - General Information A.2 Index To Charts ....A.2.01 Main Control Board (UMMB) Original ....A.2.02 Main Control Board (UMMB) Current ....A.2.03 RS232-C Serial Module (UMRS) B Illustrated Parts Listing B.1 Overview - General Information ....B.1.02 Definition of Terms Page 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 Table of Contents ....B.1.03 Parts Ordering Information B.2 Charts ....B.2.01 Printer ....B.2.02 Covers ....B.2.03 Printer Unit ....B.2.04 Printer Mechanism (1 of 3) ....B.2.05 Printer Mechanism (2 of 3) ....B.2.06 Printer Mechanism (3 of 3) ....B.2.07 Option Parts ....B.2.08 Consumables ....B.2.09 Packaging ....B2.10 Documentation ....B.2.11 Service Training Kit Revision List Page 123 124 125 126 127 128 129 130 131 132 133 134 135 Page: 2 Service Guide ML380 Chapter 0 About This Manual Manual Copyright This document may not be reproduced without the written permission of the Okidata Technical Training Group. Every effort has been made to ensure the accuracy of the information contained in this training course. Okidata is not responsible for errors beyond its control. © 1994 by Okidata All rights reserved. First Edition August, 1989 P/N 59238701 Second Edition September, 1993 P/N 59238702 Third Edition November, 1994 P/N 59238703 Written and produced by the Okidata Technical Training Group Please address any comments on this publication to: Technical Training Group Okidata 532 Fellowship Road Mount Laurel, NJ 08054-3499 Fax Number: (609) 235-2600, ext. 7034 Okilink Login Name: Technical Training OKIDATA is a registered trademark of Oki Electric Industry Company, Ltd.; marques deposee de Oki Electric Industry Company, Ltd.; marca registrada, Oki Electric Industry Company, Ltd. MICROLINE is a registered trademark of Oki Electric Industry Company, Ltd.; marque depose de Oki Electric Industry Company, Ltd. Centronics is a registered trademark of Centronics Inc. PLUG n PRINT is a registered trademark of Oki America, Inc.; marque deposee de Oki America, Inc. Epson is a registered trademark of Seiko Epson Corporation. IBM is a registered trademark of International Business Machine Corporation. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 3 Service Guide ML380 Chapter 1 Product Specifications 1.1 OVERVIEW 1.1.01 General Information The Microline 380 is an 80 column, impact dot matrix printer using a 24 pin printhead. It emulates the Epson LQ printer. A push tractor is standard. An optional pull tractor is available. Font and Character Pitch selection is available through the operator panel, printer menu, or through software (using control codes). A Centronics Parallel interface is standard. An RS232-C serial module is available as an option. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 4 Service Guide ML380 Chapter 1 Product Specifications 1.2 PHYSICAL SPECIFICATIONS 1.2.01 Dimensions Width: 15.67 inches (398 millimeters) Depth: 4.72 inches (120 millimeters) Height: 13.58 inches (345 millimeters) NOTE: Dimensions DO NOT INCLUDE the platen knob, acoustic cover, and paper separator. 1.2.02 Weight 17.9 pounds (8.1 kilograms) Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 5 Service Guide ML380 Chapter 1 Product Specifications 1.3 POWER REQUIREMENTS 1.3.01 Input Power 120 VAC: +5.5 / -15% 220/240 VAC: +5.5 / -15% Single-phase AC 1.3.02 Power Consumption Operating: 90 VA Idle: 30 VA 1.3.03 Power Frequency 120 VAC: 50/60 Hz +/- 2% 220/240 VAC: 50/60 Hz +/- 2% Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 6 Service Guide ML380 Chapter 1 Product Specifications 1.4 ENVIRONMENTAL CONDITIONS 1.4.01 Acoustic Rating 57 dBA 1.4.02 Altitude 10,000 feet (3,050 meters) 1.4.03 Ambient Temperature and Relative Humidity (RH) While operating: 41 to 95 degrees Fahrenheit (5 to 35 degrees Celsius) Operating humidity: 20% to 80% RH While in storage: -40 to 158 degrees Fahrenheit (-40 to 70 degrees Celsius) Storage humidity: 5% to 95% RH 1.4.04 Impact Non-operating: 3 G or less 1.4.05 Vibration Operating: 0.3 G (5 to 150 Hz) or less (except at resonating frequency) Non-Operating: 1 G (5 to 150 Hz) or less (except at resonating frequency) Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 7 Service Guide ML380 Chapter 1 Product Specifications 1.5 AGENCY APPROVALS 1.5.01 Listings UL No: UL Standard No. 478 and 114 CSA No: CSA Standard C22.2 No. 154 FCC: FCC Certified per Part 15, Subject J, Class B VDE: VDE 0806, 0875 Class B, and 0836 BS: BS 5850 / 6204 IEC: 435 / 380 Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 8 Service Guide ML380 Chapter 1 Product Specifications 1.6 OPERATIONAL SPECIFICATIONS 1.6.01 Character Matrix Sizes Table of Print Speed and Character Matrix Mode Speed Matrix (H x V) LQ 63 cps (12 cpi) 30 x 18 Utility 192 cps (12 cpi) 9 x 17 HS Utility 240 cps (15 cpi) 7 x 16 1.6.02 Characters Per Line Maximum Characters Per Line 80 96 120 137 160 10 12 15 17.1 20 Characters Per Inch 1.6.03 Character Pitches 5, 6, 8.5, 10, 12, 15, 17.1, 20 characters per inch Characters Per Inch = cpi The character pitches are selected through the following methods. Operator panel (front panel controls) Menu Select Mode (Menu Mode) Control codes in the software Special Microline 380 drivers 1.6.04 Character Sets Standard ASCII EPSON Character Set IBM Character Set I and II Foreign Language Sets (14) Line Graphics Zero / Slashed Zero 1.6.05 Emulation Epson LQ 1.6.06 Fonts Letter Quality Courier Letter Gothic Prestige Orator Roman Helvette Draft Utility Special Font Effects Emphasized / Enhanced Outline Shadow Double Height Double Width 1.6.07 Front Panel Switches SELECT / Exit FEED / Group TOF / PARK / Item FONT / Set PITCH / Print 1.6.08 Graphics Resolution Graphics Resolution Maximum: 180 x 360 dpi Minimum: 60 x 72 dpi *1.6.09 Interface Standard Parallel Optional RS232C Serial, 19.2 Kbytes Super-Speed (Ready/Busy, X-ON / X-OFF) NOTE: When the serial interface module is installed, the printer's parallel interface connector is NOT accessible. 1.6.10 Line Feed Increments Fixed 6 lines per inch (lpi) [0.167 inch (4.23 millimeters)] 8 lines per inch (lpi) [0.125 inch (3.175 millimeters)] Variable n/60 inch n/180 inch 1.6.11 Line Feed Time 2.2 inches per second 1.6.12 Menu Mode Print: Prints the entire menu. Group: Selects Group Function Item: Selects Item Set: Selects Item Value Exit: Exits Menu Mode, Enters Select 1.6.13 Paper Feed Methods Standard Friction Feed (Top) Push Tractor (Rear) Optional Pull Tractor (Bottom / Rear) Single-Bin Cut Sheet Feeder (Top) CSF 3800 1.6.14 Paper Feed Paths Top Feed (Standard) Rear Feed (Standard) Bottom Feed (by using an Optional feed mechanism) Special Features Paper Park Semi-Automatic Sheet Feeding Paper Tear Off 1.6.15 Paper Loading Semi-Automatic Sheet Feeding Opening the paper bail arm activates the semi-automatic sheet feeder (SASF) 1.6.16 Paper Out Detection Distance from end of paper Rear Feed: 2.3 inches (57 millimeters) Bottom Feed: 1.4 inches (36 millimeters) Top Feed: 1 inch (25 mm) 1.6.17 Paper Tear Capabilities Paper Tear-0ff (sharp edge on access cover) 1.6.18 Print Method Printhead Type General Information Impact Dot Matrix 24 pin printhead .0079 inch (.20 millimeter) diameter pins Overheat Protection When printhead temperature is between 90 and 129 degrees Celsius (ALARM 1), the printer stops bi-directional printing. Uni-directional printing begins. If the temperature continues to rise (130 degrees Celsius, ALARM 2), printing stops. Printing will resume when the printhead temperature drops below the ALARM 1 threshold. NOTE: Refer to Section Two for more information on printhead operation. Printhead Gap Information Two items factor into printhead gap information. 1. Printhead Gap Adjustment This is a SERVICE ADJUSTMENT made by a technician. It is covered in Section 3.3 of this Service Handbook. The Adjustment measures 0.016, +/- 0.002 inches (0.41, +/- 0.05 mm). 2. Printhead Gap Adjust The printhead gap is modified by moving the printhead gap lever, located on the left side of the housing. To move the lever, pull it towards the printer housing and push the lever towards the front of the printer. The settings are 1, 2, 3, 4, and 5. Use 1 for single sheet. Use 2 for multiple sheets or forms (thickness: 2 sheets). Use 3 for multiple sheets or forms (thickness: 3 sheets). Use 4 for multiple sheets or forms (thickness: 4 sheets). Use 5 for envelopes and extra thick paper. 1.6.19 Print Modes Letter Quality Utility 1.6.20 Print Speed Print Mode Character Pitch 10 cpi LQ Utility 50 cps 150 cps 12 cpi 60 cps 180 cps 15 cpi 75 cps 112.5 cps 17.1 cpi 85 cps 128.25 cps 20 cpi 100 cps 150 cps Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 9 Service Guide ML380 Chapter 1 Product Specifications 1.7 PAPER SPECIFICATIONS CAUTION: Use Bottom Feed and/or optional Pull Tractor for card stock and labels. 1.7.01 Types Card Stock Length: 3 to 14 inches (76.2 to 356 millimeters) Number of Copies: Original Paper Feed Path: Bottom Printhead Gap Information: Refer to the Printhead Gap Information, Section 1.6 Thickness: .008 inches (0.2 millimeters) Maximum Weight: 100 lbs. (375 g/m 2 ) Maximum Width: 5 to 8 inches (127 to 203 millimeters) Continuous Form Length: 3 to 14 inches (76.2 to 356 millimeters) Number of Copies: Original, Original + 2 Interleaf Original + 2 Carbonless Paper Feed Path: Rear or Bottom Printhead Gap Information: Refer to the Printhead Gap Information, Section 1.6 Thickness: Single 0.0028 to 0.0039 inches (0.07 to 0.1 millimeters) Multi 0.01 inch (.25 millimeter) Maximum Weight: Single Part 14 - 22 lb. (52.5 to 82.5 to g/m 2 ) Multi-Part, Carbonless 9 - 11 lb. (35 to 40 g/m 2 ) Multi-Part, Interleaf Paper 10 - 12 lb. (38 to 45 g/m 2 ) Carbon 9 lb. (35 g/m 2 ) Width: 3.5 to 10.5 inches (89 to 267 millimeters) Cut Sheet Number of Copies: Original, Original + 2 Interleaf Original + 2 Carbonless Paper Feed Path: Top Printhead Gap Information: Refer to the Printhead Gap Information, Section 1.6. Note: Multi-part cut sheet paper CANNOT be used. Weight: 14 to 22 lbs. (52.5 to 82.5 g/m 2 ) Width: 7.2 to 10 inches (182 to 254 millimeters) Length: 3 to 14 inches (76.2 to 356 millimeters) Thickness: 0.0028 to 0.0039 inches (0.07 to 0.1 millimeters) Envelopes Number of Copies: Original Paper Feed Path: Bottom Printhead Gap Information: Refer to the Printhead Gap Information, Section 1.6. Size: Single Feed Minimum: 6.5 x 3.6 inches (16.5 x 9.1 centimeters) Maximum: 9.5 x 4.1 inches (24.1 x 10.4 centimeters) Continuous Non-overlap type Thickness: .016 inches (41 millimeters) Maximum Weight: 17 to 24 lbs. (64 to 90 g/m 2 ) Maximum Labels Length: 3 to 14 inches (76.2 to 356 millimeters) Number of Copies: Original Paper Feed Path: Bottom Printhead Gap Information: Refer to the Printhead Gap Information, Section 1.6. Weight: N/A Width: Carrier 3.5 to 8.5 inches (88 to 261 millimeters) Thickness: .01 inches (0.25 mm) Maximum (including backing) CAUTION: Use Bottom Feed and/or optional Pull Tractor for card stock and labels. DO NOT use fabric labels. DO NOT print on the edge or perforation of the label. DO NOT use Paper Park with labels. Transparency NOTE: Roller marks may mar the transparency under high temperature / high humidity conditions. Length: 3 to 14 inches (76.2 to 356 millimeters) Number of Copies: Original Paper Feed Path: Top Printhead Gap Information: Refer to the Printhead Gap Information, Section 1.6. Weight: 12 to 24 lbs. (45 to 90 g/m 2 ) Width: 8.5 to 11 inches (216 to 280 millimeters) Thickness: 0.004 inches (0.1 millimeters) Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 10 Service Guide ML380 Chapter 1 Product Specifications 1.8 MEMORY SPECIFICATIONS 1.8.01 EEPROM 256 Kbit EEPROM Used to store Menu data Located at Q18 of the main control board 1.8.02 ROM Program ROM 256 Kbit Located at Q2 of the main control board Resident Character Generator ROM 1 Mbit Masked to the CPU 1.8.03 RAM 32 Kbyte Located on the main control board Used as Receive Buffer Printer Buffer Scratch Pad Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 11 Service Guide ML380 Chapter 1 Product Specifications 1.9 CONSUMABLES 1.9.01 Ribbon CAUTION: Using a non-Okidata ribbon may damage the printhead and void any warranties. Material Cartridge Fabric Types Black Nylon Ribbon Life (On average, at 10 characters per inch, Utility Mode) Black Ribbon 2 million characters Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 12 Service Guide ML380 Chapter 1 Product Specifications 1.10 OPTIONS 1.10.01 Cut Sheet Feeders CSF-3800 Single Bin with envelope capability Paper Width: 7.2 to 8.5 inches 182 to 216 millimeters Paper Length: 10.1 to 11.7 inches 257 to 297 millimeters Capacity: 50 sheets (20 lb.) 1.10.02 Pull Tractor Kit Bottom Feed Rear Feed (For Push/Pull Operation) Paper Types: Continuous Feed and Labels 1.10.03 Serial Interface Super-Speed 19.2K RS-232C Ready/Busy/X-On/X-Off Protocols Can be configured through the Menu When the serial interface module is installed, the printers parallel interface connector is NOT accessible. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 13 Service Guide ML380 Chapter 1 Product Specifications 1.11 RELIABILITY 1.11.01 Mean Time Before Failure (MTBF) Approximately 4,000 hours: 25% duty cycle / 35% page density 1.11.02 Mean Time To Repair (MTTR) Approximately 15 minutes to major sub-assembly level 1.11.03 Printer Life Approximately 12,000 hours of power-on time: 25% duty cycle / 35% page density 1.11.04 Printhead Life Average 200 million characters in 10 cpi utility mode @ normal 25% duty, 35% page density 1.11.05 Ribbon Life Approximately 2 million characters in 10 cpi mode 1.11.06 Warranty (Limited) One year, parts, labor, and printhead 1.11.07 Service Authorized Okidata Service Centers Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 14 Service Guide ML380 Chapter 2 Principles of Operation 2.1 ELECTRICAL OPERATION 2.1.01 General Information The control board consists of the microprocessor and its peripheral circuits, the drive circuits, DC power supply circuit and interface connector. The switches and LED's of the operator panel are mounted on this board. The power to the control board is supplied by the power supply unit. The power to the other electrical parts is distributed via the connectors on the control board. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 15 Service Guide ML380 Chapter 2 Principles of Operation 2.1.02 Microprocessor and Peripheral Circuits Microprocessor (Q5: 83C154GS-551-V1K) The microprocessor is the nucleus of the control circuit. Its peripheral circuits operate under program control by this microprocessor. The I/O ports of the microprocessor are connected to the address bus, data bus, and control lines. Program ROM (Q2) The program ROM (256 Kbit) contains the control program for the printer. The microprocessor operates by execution of this program. RAM (Q4) The RAM stores received data (to be printed). (32 Kbytes) CGROM (Q3) 1 MBit ROM which stores the resident character fonts. EEPROM (Q18) This 256-bit serial Electrically Erasable and Programmable ROM stores the Menu Mode data. LSI (Q7: LC92018B-283) This LSI switches the phase of the space motor, and generates the timing of print dots for each print density. The LSI performs the following functions. Space Pulse Motor Control To obtain the carriage speed instructed by the microprocessor, the LSI generates the pulse switch timing and overdrive time. Dot Timing generation Parallel Interface Control LF Motor Control LED Drive General Purpose Input Port Used to read Operator Board Switches. LSI (Q6: LC92011B-284) This LSI drives the 24 pin printhead and controls memory. The following describes the function of the LSI. Printhead Drive Control Head Pin Counting Function Counts the number of printwires to be driven then, changes the duration of the HD ON signal accordingly. Memory Control Extends the addressable memory by switching banks in/out. LED Drive Output Port Microline 380 Block Diagram Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 16 Service Guide ML380 Chapter 2 Principles of Operation 2.1.03 Initialization The printer is initialized whenever it is powered ON or when the I-PRIME signal is received at the parallel interface. Initialization is started when the RST-P signal is sent from the reset circuit (Q8:Pin 1) to Q5, Q6 and Q7. When RST-P is generated, ROM program execution starts with the mode setting of Q5, Q6 and Q7. Next, ROM and RAM are checked for errors, RAM is initialized and the carriage is homed. The program finally establishes the Interface signals (output level of ACK, BUSY, etc.), switches the SELECT indicator ON, and informs the host computer that the printer is ready to receive data. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 17 Service Guide ML380 Chapter 2 Principles of Operation 2.1.04 Interface Control Parallel Interface The data from the interface is received through connector (CN-1) and the Interface LSI (Q7) latches this data in sync with the STB signal. The BUSY signal is switched ON as the data is processed. When processing is completed, the BUSY signal is switched OFF and an ACK signal is sent to the host to request more data. The BUSY signal is also switched ON when the printer is not able to receive data (buffer is full, printer is deselected or an error condition exists). Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 18 Service Guide ML380 Chapter 2 Principles of Operation 2.1.05 Printhead Drive Circuit This circuit is used to drive the 24 print wires. The signals HD1 through HD24 control the individual print wires. The HD ON signal (even/odd trigger) enables the drive circuit when printing is desired. The head drive duration is determined by an RC integrating circuit which modifies the HD ON pulsewidth. The pulsewidth of the HD ON signal varies with the number of pins being driven. The drive time increases as more pins are driven, and decreases as fewer pins are driven. The RC circuit compensates for the fluctuation of drive voltage (+35 vdc). Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 19 Service Guide ML380 Chapter 2 Principles of Operation 2.1.06 Spacing Drive Circuit The space motor is driven by a two-phase pulse motor. The phase signals (Phase 1, Phase 2, Phase 3 and Phase 4) and the basic pulse signals are output from the LSI (Q7). The pulse signals are modified by the drive voltage compensation circuit and sent back to the LSI (Q7). The space overdrive signals (Phase 1DVOV, Phase 2 DVOV, Phase 3DVOV and Phase 4DVOV) switch Q16 and Q17 ON, setting up the proper phase relationship of analog space motor drive signals (SP Phase 1 through SP Phase 4). These signals are then sent to the space motor. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 20 Service Guide ML380 Chapter 2 Principles of Operation 2.1.07 Line Feed Circuit The line feed motor shaft is held stationary by + 8 vdc (the holding current is approximately 30 ma) whenever in a stopped position. During line feed operation, the line feed motor is driven in accordance with the LF OVD signal. The signals LFMO Phase 1 through LFMO Phase 4 establish the proper phase relationship for driving the motor. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 21 Service Guide ML380 Chapter 2 Principles of Operation 2.1.08 Alarm Circuits Fault Alarm Circuit (in Power Supply Unit) This protective circuit causes the AC fuse to open when a fault occurs in the printhead drive circuit or line feed drive circuit, thus preventing component failure. To accomplish this, the circuit monitors the overdrive signal of each drive circuit. If the duration of any drive circuit exceeds a predetermined time, the appropriate signal (HEAD ALM, LF ALM1 or LF ALM2) will be sent to the fault alarm circuit. The fault alarm circuit generates the ALM signal (high), which switches on an SCR. This causes the secondary coil (40 volts) of the main transformer to short-circuit, causing an overcurrent to flow through the primary coil and open the AC fuse. Printhead Overheat Alarm Circuit In order to protect the printhead coils, this circuit monitors the printhead temperature by using a thermistor contained in the printhead. The CPU senses this circuit every time a line is printed. Whenever printing, the printhead temperature increases. If the head temperature reaches approximately 90 degrees - 129 degrees Celsius, a head overheat ALARM 1 is generated. When ALARM 1 is detected, bi-directional printing stops. Uni-directional printing begins. If the printhead temperature continues to increase (130 degrees Celsius), ALARM 2 is generated. Printing stops until the head temperature decreases. When the head temperature drops below the ALARM 1 threshold, printing resumes. Low DC Voltage Detection Circuit The + 35 vdc drive voltage is monitored for a low voltage condition during each print operation. If the + 35 vdc drops, the negative terminal input voltage of the comparator (Q8) decreases, the comparator reverses state, and the DC LOW-P signal is switched ON. When the signal DC LOW-P is active, printing is accomplished by using twelve of the twenty-four printwires in a dual-pass print. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 22 Service Guide ML380 Chapter 2 Principles of Operation 2.1.09 Paper End Detection Circuit PAPER END is detected by a photosensor. When the printer detects an out-of-paper condition, the PEN signal goes low, printing is stopped, and the ALARM LAMP is switched ON. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 23 Service Guide ML380 Chapter 2 Principles of Operation 2.1.10 Power Supply The power supply consists of the power transformer, the filter board and the DC power supply circuit on the control board. The AC input voltage is transformed into 8.6 VAC and 46 VAC by the power transformer. These AC voltages are converted to + 8 vdc, + 5 vdc and + 35 vdc levels by the DC power supply circuit on the control board. The + 5 vdc is a regulated voltage. Filter Board The filter board consists of the power switch, AC fuse and AC noise filter. Power Transformer If the internal temperature of the power transformer rises abnormally, the built-in temperature fuse will open to prevent any damage to other electrical components. NOTE: If the temperature fuse in the transformer opens, the transformer must be replaced. Power Supply Circuit Converts the AC Voltage input to + 8 vdc, + 5 vdc and + 35 vdc and supplies it to the control board. This circuit also regulates the + 5 vdc. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 24 Service Guide ML380 Chapter 2 Principles of Operation 2.2 MECHANICAL OPERATION 2.2.01 Printhead Mechanism The Microline 380 uses a highly efficient stored energy type printhead. Power is not consumed until the printwires are activated, thereby extending the printhead life to approximately 200 million characters. The printhead uses 24 printwires (two columns of 12 wires each). Each wire is welded to an armature. Behind this armature is a spacer ring. Each of the 24 printwire armatures have a permanent magnet behind them. The magnets attract the armatures, drawing the printwires into the wire guide, thus keeping the wires inside the printhead. A coil is wrapped around each of the permanent magnets. When a dot is to be printed, current is passed through the appropriate coil. This creates a magnetic field which counters the magnetic field of the permanent magnet. The armature can then spring forward and the print wire (which is attached to the armature) strikes the ribbon and imprints a dot on the paper. When current is removed from the coil, the magnetic field of the permanent magnet attracts the armature, causing the printwire to retract into the wire guide once again. The printhead contains a built-in thermistor used to monitor the printhead temperature. The printhead is composed of the following parts. Wire Guide Print Wires Armature Assembly Yoke Spring Spacer Magnet Assembly Thermistor Printed Circuit Board Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 25 Service Guide ML380 Chapter 2 Principles of Operation 2.2.02 Spacing Spacing is performed when the main shaft (installed in parallel with the platen), and carriage (mounted on the space rack) are driven by the pulse motor. Spacing involves the parts listed below. Pulse Motor Drive Pulley Idle Pulley Carriage Shaft Carriage Frame Space Rack Spacing Operation The carriage containing the printhead moves parallel to the platen along the main carriage shaft and space rack. Power from the space motor is transferred via the mini-pitch belt, which is attached to the bottom of the carriage frame. When the pulse motor rotates clockwise (as viewed from above), the driving force is transmitted to the mini pitch belt through the drive pulley, and the carriage moves from left to right. The carriage is designed to move 0.8 inch when the pulse motor performs one rotation. Head Gap Adjusting The head gap adjusting mechanism adjusts the gap between the platen and printhead. This is accomplished by moving the adjusting lever on the left side of the printer mechanism. When the lever is moved, the carriage shaft rotates. Since the carriage shaft is attached to the printer mechanism with eccentric collars, as the carriage shaft rotates, the distance between the platen and carriage shaft changes. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 26 Service Guide ML380 Chapter 2 Principles of Operation 2.2.03 Ribbon Drive The ribbon drive mechanism moves the ribbon in synchronization with the space motor operation. The ribbon drive mechanism consists of the following items. Ribbon Drive Gear assembly Space Rack Ribbon Cartridge Ribbon Cartridge An endless ribbon with a single direction feed is used. Ink is supplied from an ink tank, which is built into the ribbon cartridge. Ribbon Feed Operation The rotation of the space pulse motor is transmitted to the drive gear in the ribbon cartridge through the space rack and ribbon feed gear assembly, thereby feeding the ink ribbon. The feed direction of the ribbon is maintained by switching the rotational direction of the gears in the ribbon drive assembly. This ensures uni-directional ribbon movement when bi-directional printing is used. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 27 Service Guide ML380 Chapter 2 Principles of Operation 2.2.04 Paper Feed Paper feeding is performed by turning the platen and the pin tractor. The tractor is driven by the line feed pulse motor. The paper feed mechanism consists of the following items. Pulse motor with gears Idler Gear Change Spring Change Gear Platen Tractor Feed Unit Pressure Roller Assembly Friction Feed When the release lever is set to the FRICTION FEED position, the change gear is disengaged from the tractor gear. At the same time, the release lever applies pressure to push the pressure rollers against the platen, allowing paper to be fed. Tractor Feed When the release lever is set to the TRACTOR FEED position, the release lever allows the reset spring to push the change gear toward the tractor gear. At the same time, the release lever pushes the pressure rollers away from the platen, allowing paper to be fed by the tractors. NOTE: Drive power from the line feed motor is transferred from the platen to the idler gear and then to the change gear. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 28 Service Guide ML380 Chapter 2 Principles of Operation 2.2.05 Paper-End Detection Continuous Sheet Paper-End When continuous sheet paper is installed, the paper moves the continuous sheet paper-end lever to A1 and the sensor is switched ON. When out of continuous sheet paper, the paper-end lever moves to position B1 and the sensor is switched OFF indicating a paper-end condition. Bottom Feed Paper-End When paper is installed, it moves the bottom paper-end lever to position A2 and the sensor is switched ON. When a paper out condition exists, the bottom paper-end lever moves to position B2 and the sensor is switched OFF, indicating a paper-end condition. Cut-Sheet Paper-End When cut-sheet paper is installed, the paper moves the cut-sheet paper-end lever to position A3 and the sensor is ON. At the end of printing, the cut-sheet paper-end lever moves to position B3 and the sensor is switched OFF, indicating a paper-end condition. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 29 Service Guide ML380 Chapter 2 Principles of Operation 2.2.06 Semi-Automatic Sheet Feeder (SASF) The Semi-Automatic Sheet Feeder (SASF) is used to automatically set the print start position when using cut-sheet or continuous sheet paper. The procedure is as follows. Cut-Sheet SASF 1. Push the paper release lever to the cut-sheet side (rear of printer). 2. Insert the paper from behind the platen. 3. Open the paper bail arm (pull toward the front of the printer). This activates the SASF switch. 4. Line feed operation will feed the paper 2.76 inches. If the paper does not move, the SASF motion becomes invalid and is treated like an ordinary paper-end. 5. Once the paper bail arm is closed, a reverse line feed of about 0.18 inches is performed. This moves the paper to the print start position. Continuous Sheet (Rear Feed) SASF 1. Push the paper release lever to the continuous sheet side (front of the printer). 2. Insert the paper into the push tractor. 3. Open the paper bail arm (pull toward the front of the printer). This activates the SASF switch. 4. Line feed operation will feed the paper 3.6 inches. If the paper does not move within 2.4 inches of motion, the SASF motion becomes invalid and this is treated like an ordinary paper-end. 5. Once the paper bail arm is closed, a reverse line feed of about 0.18 inches is performed. This moves the paper to the print start position. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 30 Service Guide ML380 Chapter 2 Principles of Operation 2.2.07 Paper Park Paper park operates as follows. 1. Press PAPER PARK. 2. Reverse line feed retracts the paper until a PAPER-END condition exists or 14 inches of paper have been fed. 3. When the PAPER-END condition exists, the printer retracts 0.49 inches of paper. The paper is still installed on the push tractor, but cut sheet paper may now be fed. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 31 Service Guide ML380 Chapter 3 Maintenance & Disassembly 3.1 OVERVIEW 3.1.01 General Information This section lists the parts replacement, adjustment, cleaning, lubrication, and shipping procedures. Disassembly should not be performed unless absolutely necessary. NEVER perform disassembly on a malfunctioning printer until you have followed the failure analysis procedures in Section Four of this Service Handbook. Follow the procedures listed in Adjustments and Service Settings. Adjustments may be required when either consumable or parts are replaced. Failure to perform these procedures could result in unnecessary service calls. Proper performance of maintenance and cleaning will help to achieve the best possible print quality from the printer. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 32 Service Guide ML380 Chapter 3 Maintenance & Disassembly 3.1.02 Maintenance Tools The following tools are required to service the printer. #2 Phillips Screwdriver (with magnetic tip) Straight-slot Screwdriver Needle Nose Pliers (4 Inch) Awl or large, opened paper clip Wire Cutters Digital Multimeter Feeler Gauge (capable of measuring .014 inches) Shop Vacuum Clean, soft, and lint-free Cloth All-Purpose Cleaner Contact Kleen (Okidata P/N 51802301) Platen Cleaner Machine Grease Machine Oil Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 33 Service Guide ML380 Chapter 3 Maintenance & Disassembly 3.1.03 Maintenance Precautions 1. Do not disassemble the unit if it is operating normally. 2. Before starting disassembly and assembly, always turn the AC power switch OFF and pull out the AC plug. 3. Detach the interface cable, if installed. 4. Do not remove parts unnecessarily. Try to keep disassembly to a minimum. 5. Use the recommended maintenance tools. 6. When disassembling, follow the listed sequence. Failure to follow the correct sequence may result in damaged parts. 7. Since screws, collars and other small parts are easily lost, they should be temporarily attached to the original positions. 8. When handling circuit boards use extreme care. Integrated circuits (microprocessors, ROM, and RAM) can be destroyed by static electricity. 9. Do not place printed circuit boards directly on conductive surfaces. 10. Follow the recommended procedures when replacing assemblies and units. 11. Perform the printhead gap adjustment procedure when any of the following occur. Refer to Section 3.3 of this Service Handbook. Print Quality is darker on one side of the document. Parts are replaced. Printhead (3.2.02) Space Rack (3.2.04) Carriage Frame (3.2.13) 12. Perform the space belt tension adjustment procedure when the following parts are installed. Refer to Section 3.3 of this Service Handbook. Space Belt (3.2.06) Space Motor Assembly (3.2.22) Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 34 Service Guide ML380 Chapter 3 Maintenance & Disassembly 3.2 DISASSEMBLY/ASSEMBLY PROCEDURES General Information This section contains the printer disassembly procedures. Only the removal procedures are explained here. Reverse the procedure for the installation. At the bottom of each procedure is a listing of the parts covered in that procedure. The Okidata part number, item description, comment (RSPL, Option, Consumable) and cross-reference to Appendix B is provided for each part. Items included in the Recommended Spare Parts List are indicated by the acronym RSPL. N/A will appear where a part number is not available. Part Item Comment Appendix B Number Description Reference This Service Handbook lists the disassembly procedures for major components of the unit. Okidata DOES NOT recommend disassembling a unit which is operating normally. If you decide to perform disassembly during this training, Okidata recommends that you perform only the disassembly procedures for RSPL items. All other procedures are provided to assist you in identifying parts. It is not likely that you will perform these procedures while servicing the unit. Be sure to read all notes, cautions, and warnings, as they contain important information regarding disassembly / assembly. Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business Partner Exchange (BPX) for any updates to this material. (http://bpx.okidata.com) Page: 35 Service Guide ML380 Chapter 3 Maintenance & Disassembly 3.2.01 Paper Separator 1. Raise the access cover (1). 2. Move the bail lever (2) toward the front of the printer. 3. Push the paper separator (3) at location A and release it from the platen shaft (4). 4. Lift the paper separator to detach the guide pins (5) from the printer mechanism (6). P/N N/A AC Cable B.2.03 P/N 53511401 Separator: Paper RSPL B.2.03 Copyright 1997, Okidata, Division of OKI America, Inc. All rights reserved. See the OKIDATA Business