G E N I C O M M a t r i x P r i n t er LA36 Service Manual GENICOM Corporation
REVISION RECORD Edition 001 Date published FEB 2000 Page – Revised contents First issue The contents of this manual may be revised without prior notice. All Rights Reserved, Copyright © 2000 GENICOM Corporation. No part of this manual may be reproduced in any form without permission.
PREFACE This manual is for engineers who operate, install, or maintain the GENICOM Matrix Printer LA36N/LA36W.
CONTENTS CHAPTER 1 PRINTER SPECIFICATIONS, PERFORMANCE, AND CONFIGURATION ............. 1-1 1.1 Overview ................................................................................................................................................... 1-1 1.2 Equipment Structure .................................................................................................................................. 1-2 1.2.1 Overview ..............................................................................
4.9 Level 2 Maintenance ................................................................................................................................. 4-6 4.9.1 Parts replacement ................................................................................................................................ 4-6 (1) Acoustic cover replacement ....................................................................................................... 4-7 (2) Tractor unit replacement ..........................
4.10 Diagnostics .............................................................................................................................................. 4-48 4.10.1 Self-test printing ................................................................................................................................ 4-48 (1) Starting self-test printing ............................................................................................................ 4-48 (2) Checking printer performance .....
5.3.7 Ribbon shift control ............................................................................................................................ 5-35 5.3.8 Fire check control ............................................................................................................................... 5-37 (1) Short-mode detection ............................................................................................................... 5-37 (2) Long-mode detection ...............................
ILLUSTRATIONS Figure 1.1 LA36N and LA36W printers ......................................................................................................... 1-1 Figure 1.2 Printer component structure ........................................................................................................... 1-3 Figure 1.3 Upper cover assembly (LA36N) .................................................................................................... 1-4 Figure 1.4 Printer lower assembly (LA36N) ..............
Figure 5.26 Phase switching and carriage drive direction .............................................................................. 5-28 Figure 5.27 Relationship between carriage drive speed and phase excitation ................................................ 5-29 Figure 5.28 Carriage drive 1/2-phase excitation at low speed ........................................................................ 5-30 Figure 5.29 Carriage drive 2-phase excitation at high speed ...........................................
TABLES Table 3.1 Errors indicated by the Fault indicator and the buzzer ................................................................... 3-15 Table 3.2 Alarms that turn power off .............................................................................................................. 3-15 Table 4.1 Maintenance tools ........................................................................................................................... 4-2 Table 4.2 Parts not to be disassembled .............
CHAPTER 1 PRINTER SPECIFICATIONS, PERFORMANCE, AND CONFIGURATION 1.1 Overview This manual is for maintenance engineers, and covers overall maintenance of the Matrix Printers LA36N and LA36W, together with detailed information such as troubleshooting and component replacement. The information in this manual applies both to the Matrix Printer LA36N (80-column printer) and to the Matrix Printer LA36W (136-column printer). However, illustrations are of Matrix Printer LA36N unless otherwise stated.
1.2 Equipment Structure 1.2.1 Overview This section outlines printer structure and features. 1.2.2 Model configuration There are two basic models. The LA36N is an 80-column printer and the LA36W a 136-column printer. Each model has two optional components: power supply and color kit (color ribbon shift mechanism).
1.2.3 Structure Major printer components are organized as shown below. Items in boldface are recommended spare parts (see Chapter 6) that can be replaced in the field by maintenance service engineers. Replacement and adjustment are detailed in Chapter 4. LA36N/W printer Upper cover assy Upper cover Front cover Top cover (bail rollers are built in for LA36W) Acoustic cover [soundproof cover] Control panel [OP board] Note: [ ] indicates a name referred to in the Recommended Spare Parts List.
(1) Upper cover assembly The screws (two for the LA36N and three for the LA36W) on the back, fasten the upper cover to the bottom cover. The upper cover assembly consists of the upper, front, and top covers, an acoustic cover, and a control panel –– all plastic, lightweight, and sturdy. The cut-sheet stand is mounted on this assembly.
f. Cut-sheet stand The cut-sheet stand catches printed pages ejected by the printer. It must be raised while printing cut sheets and laid down while printing continuous forms. It must also be raised while printing paper-stapled continuous forms in push-tractor mode. g. Back cover The back cover, which is installed on the cut-sheet stand, is opened to set continuous forms on the tractor unit from the back of the printer. It must be closed while the printer is operating.
(3) Lower cover assembly Power supply Bottom cover Printer control board Figure 1.4 Printer lower assembly (LA36N) a. Bottom cover The bottom cover supports the printer mechanism. b. Printer control board The printer control board controls the host interface, control panel, and printing mechanism, using an MPU and an LSI. Memory holds resident character patterns and firmware, including resident emulation programs. This board has drivers and receivers for other components.
CHAPTER 2 UNPACKING, PERFORMANCE CHECK, AND CONNECTION The contents of this chapter are briefly reproduced from the Setting the Installation Guide for reference in maintenance although the contents are originally for users of the LA36N and LA36W printers. 2.1 Overview The LA36N and LA36W printers come packed for transportation. After unpacking and before installation, the printer must undergo self-test printing. Installation requires minimum time and expense. 2.
2.3 Unpacking Unpack the printer as follows (Figure 2.1): 1. Open the carton and remove accessories — the Installation guide, CD-ROM, cut-sheet stand, platen knob, power cord (100 –120 or 220 –240 VAC), serial interface cable, and ribbon cartridge. 2. Lift out the printer together with its packing cushions (not shown in the figure). Remove cushions and place the printer carefully on a level, vibration-free surface.
3. Remove tape securing the acoustic cover. Adhesive tape is applied along the front edge of the acoustic cover. For LA36W printers, two adhesive tapes are applied at the back of the acoustic cover. 4. Open the front cover and remove the print head shipping restraint (cardboard). Cardboard Front cover Figure 2.2 Removing the print head shipping restraint (cardboard) 5. At the back of the printer, remove the two tractor unit securing adhesive tapes [A].
2.4 Inspection after Unpacking 1. Carefully check the printer and the accessories for visible damage. 2. Install the cut-sheet stand (Figure 2.4). The cut-sheet stand enables smooth feeding of not only cut sheets but continuous forms, and its paper guides position cut sheets for printing. 3. Install the platen knob. 4. Install the ribbon cartridge. See the Installation Guide for details. 5.
CHAPTER 3 TROUBLESHOOTING This chapter helps pinpoint the causes of problems with the printer. Sections 3.1 to 3.5 are troubleshooting diagrams. The flowcharts show how to determine what is wrong with the printer and what to do to correct the problem. Section 3.6 explains error displays on the control panel that help clarify the cause of a problem. For replacement and adjustment after recovery, see Chapter 4.
Figure 3.1 shows printer functional components and connecting cables without showing their names since locating the connectors is easy. Printer Gears Printing mechanism Sensors LF motor 100-120 VAC or 220-240 VAC Color ribbon shift motor SP motor Print head Power supply Centronics (parallel) Printer control board To computer RS-423 board RS-423 (serial) Control panel Note: indicates a cable and connector. Figure 3.1 Printer functional block diagram a.
e. Power supply The power supply provides power for operating the printer. Its specifications depend on the input AC voltage. f. Color ribbon shift motor (user option) The color ribbon shift motor, installed on the print head cartridge, enables printing in seven colors, if supported by software. It uses either four-color cartridges or black ribbon cartridges.
3.1 All Indicators Don't Light The flowchart below shows what to do if all indicators don’t light. All indicators don’t light. Does the mechanism move? Yes The control panel is defective. No No Is the power switch turned on? Turn on the power switch. Yes Is the power plug disconnected from the receptacle? Yes Turn off the power switch, then insert the power plug into the receptacle. No Turn off the power switch, and then remove the AC fuse. Is the fuse blown? Yes Replace the AC fuse.
Continued from the previous page Unplug the AC input cord from the printer power connector, then check again AC voltage supplied to the printer. Is it correct? No Replace the AC power cord. Yes Are all connectors to the printer control board connected? No Connect connectors. Yes Do voltage check.
3.2 No Print Head Movement The flowchart below shows what to do if the print head does not move even though certain indicators light. The Fault indicator lights but the print head does not move. Does the buzzer sound continuously? Yes Defective printer control board (ROM/RAM error) No Are all connectors to the printer control board connected? No Connect connectors. Yes Turn off the power switch, unplug the interface cable, and turn on the power switch again.
The Fault indicator lights and the buzzer sound once. Yes Are continuous forms in the printer? No Set continuous forms in the printer and press the FF/Load button. Is the Fault indicator off? Yes Recovered No Push and release the paper end feeler equipped on the right-hand tractor. Does the sensor shield lever move up and down? No Replace the paper end detection link mechanism. Yes Are the paper end sensor block dusty with paper particles? Yes Clean the sensor block.
No printing online Is the interface cable connected? No Connect the interface cable. Yes Is the interface cable OK? No Replace the interface cable. Yes Is the RS-423 interface used? No (Centronics) See page 3-5, DC voltage check. Yes Is the selected protocol OK? No Use the correct protocol. Yes Is the selected baud rate OK? No Use the correct baud rate. Yes Is the selected data length OK? No Use the correct data length. Yes Is the selected data format OK? No Use the correct data format.
3.3 Incorrect Printing due to Defective Nonvolatile RAM If the printer uses defective nonvolatile RAM or the contents of nonvolatile RAM are written incorrectly, unexpected phenomena will occur. For example: • Printing is not performed even though no error is apparently detected. This may be caused when the interface type specified is the Centronics parallel, but the RS-423 serial interface is mistakenly selected internally. • Printing is not done in specified columns.
3.4 Printing Quality Abnormal The flowchart below shows what to do if the printing quality is not good. Printing quality is poor. Is the paper thickness lever set properly? No Set the lever correctly. Yes Is the print head installed correctly? No Remove the print head and install it correctly. Yes Is the ribbon cartridge installed properly? No Install the ribbon cartridge correctly. Yes Is the ribbon worn out, or ink too thin? Yes Turn off power and change the ribbon cartridge.
Continued from the previous page Are several character dots missing? Yes See page 3-12. No Is self-test printing normal? See Section 4.10.1 for self-test. No • Defective printer control board • Defective power supply board Yes Is the interface cable connected correctly? No Plug in the connector correctly. Yes Is the interface cable OK? No Replace the cable. Yes Is data OK? Use hex dump mode. See Section 4.10.2. Yes Check the host computer.
Dot missing Replace the print head. Is printing done correctly? Yes Recovered No Is the carriage cable connected correctly? No Plug in the carriage cable correctly. Yes • Defective printer control board • Defective carriage cable Color mixing abnormal Is the ribbon cartridge installed correctly? No Install the ribbon cartridge correctly. Yes Is the paper thickness lever set correctly? No Set the paper thickness lever correctly. Yes Is the color kit installed correctly? See Section 5.2.6.
3.5 Forms Feed Abnormally The flowchart below shows what to do if forms feed incorrectly. Abnormal forms feed Are forms fed? Yes See page 3-14. No Press the FF/Load button. Are forms fed? Yes No abnormality No Are forms positioned correctly? No Load forms correctly. Yes Is the paper feed motor cable connected correctly? No Connect the cable correctly.
Forms are fed but there is still a problem. Is the paper thickness lever set correctly? No Set the paper thickness lever correctly. Yes Is the paper select lever set correctly? No Set the paper select lever correctly. Yes Are forms fed smoothly? Yes See the entry below. No Are unspecified or abnormal forms used? Yes Replace forms with specified or regular forms. No Are forms positioned correctly? No Load forms correctly.
3.6 Error Display This printer indicates errors on the panel using a combination of the Fault indicator and the buzzer. Possible error combinations are described below: Table 3.1 Errors indicated by the Fault indicator and buzzer Fault indicator Buzzer sound Error cause Action for recovery from error Lighting steadily Sounds once Paper end detection See page 3-7. Flashing Sounds once Low voltage error Check DC voltage (see page 3-5).
CHAPTER 4 MAINTENANCE This chapter explains the maintenance levels 1, 2, and 3 for cleaning, lubrication, inspection, and adjustment of the LA36N and LA36W printers. 4.1 Overview Designed using the latest technology, the LA36N/LA36W printer offers high reliability and easy maintenance. Parts requiring lubrication and adjustment have been reduced and the replacement of defective parts made easier than in previous models.
4.3 Maintenance Tools Table 4.1 lists the tools required for maintenance. Table 4.1 Maintenance tools No Tool 1 2 3 4 5 6 7 8 9 10 Screwdriver M3–M5 (+) Screwdriver M2–M2.5 (+) Screwdriver M3–M4 (–) Tweezers Spring hook Long-nosed pliers Thickness gage (0.
4.6 Parts Drawings This section gives basic components and their location. Paper select lever Sensor (cut sheet) Paper feed motor Card guide Space motor Print head Platen roll Tractor (not visible) Timing belt Carriage Front stay Stay shaft Power supply Bottom cover Printer control board Figure 4.
4.7 Parts That Must Not Be Disassembled This section gives the locations of parts that must not be disassembled. Table 4.2 lists components not to be disassembled and mounting screws not to be loosened or removed. Table 4.
4.8 Level 1 Maintenance Level 1 maintenance includes only cleaning and lubrication. This can be performed without removing covers although Figure 4.3 shows the printer with the covers removed. Check inside the LA36N/LA36W printer for paper particles, dust, and dirt, and remove these as explained below. After cleaning, lubricate moving parts. Table 4.3 Cleaning Location Procedure Remarks Paper feed path Remove paper particles and dirt. Print head Remove pieces of paper and dirt from the ribbon.
4.9 Level 2 Maintenance Level 2 maintenance includes lubrication, adjustment, and parts replacement. Level 1 maintenance should be done at the same time as level 2 maintenance. 4.9.1 Parts replacement Remember the following notes when replacing any component. • Keep assembly areas clean. • Turn off power to equipment and unplug it before disassembly or assembly. • Follow procedures carefully. Do not disassemble parts that are not to be disassembled.
(1) Acoustic cover replacement Removal Raise the acoustic cover vertically (the flat surface of the mounting pin orients vertically) and lift the acoustic cover to disengage it from the top cover. Acoustic cover Installation Hold the acoustic cover vertically. Then, push the mounting pins on both side of the acoustic cover into the hook of the top cover. After that, close the acoustic cover.
(2) Tractor unit replacement a. Push tractor Removal 1. Raise the cut-sheet stand and the back cover together. 2. Pull up both ends of the tractor unit to detach the catches of the tractor unit from the support studs. Then pull the tractor unit. Catches Support studs Installation Place the catches of the tractor unit onto the support studs, push the tractor unit toward the front of printer, and snap down the tractor unit into place.
b. Pull tractor Removal Hold both sides of the tractor unit and lift and release it from the support studs.
Installation Position the catches of the tractor unit on the support studs near the platen shaft, push the tractor unit toward the front of the printer, and snap down the tractor unit into place so that the catches click on the rear studs.
(3) Cover replacement, including platen knob Removal 1. Remove the acoustic cover (Section 4.9.1(1)). 2. Remove the tractor unit (Section 4.9.1(2)). 3. Pull off the platen knob. 4. Open the front cover and the top cover nearly vertically (A), then lift and remove them together (B).
5. Raise the cut-sheet stand and the back cover together, then remove them in the direction of the arrow (A).
6. Remove the ribbon cartridge. 7. Remove the screws (two for LA36N; three for LA36W). 8. Lift the back part of the upper cover. 9. Disconnect the control panel cable from the printer control board and remove the control panel cable from the cable holder. 10. Remove the upper cover.
Installation Install covers in reverse order of removal. Notes: Be sure that the control panel cable is inserted behind the cable holder. Check that the paper thickness lever fits into the copy control lever. Check that the side cover is in place. Make sure that the box tab on the upper cover fits the hook of the bottom cover. Then, tighten the upper cover.
(4) Control panel replacement Removal 1. Remove the tractor unit (Section 4.9.1 (2)) and covers (Section 4.9.1 (3)). 2. Turn the upper cover upside down and the remove the two screws. 3. Remove the control panel. Control panel Leaf spring Upper cover Installation Install the control panel in reverse order of removal. Notes: When replacing the control panel, be careful not to bend the tape cable connected with the control board.
(5) Printing mechanism replacement Removal 1. Remove the tractor unit (Section 4.9.1 (2)) and covers (Section 4.9.1 (3)). 2. Remove the two screws. 3. Steadying the printing mechanism, disconnect the six connectors from the printer control board: Print head cables: CNHEAD1, CNHEAD2, CNHEAD3 Line feed motor wire cables: CNLF Space motor wire cable: CNSP Sensor wire cable: CNDET 4. Remove the printing mechanism.
(6) Power supply and fuse replacement Removal 1. Remove the fuse from the power supply, if necessary. 2. Disconnect AC and CNPW connectors. 3. Remove the four screws (three screws for LA36W) then remove the power supply. The rod and its securing screw are not used for LA36W. Fuse (*) power supply CNPW connector AC connector Rod (LA36N only) Installation Install the power supply and fuse in reverse order of removal.
(7) RS-423 board replacement Removal 1. Remove the two screws using the screwdriver M2-M2.5 (for Phillips screws). 2. Unplug the CNRS connector from the control board, then remove the RS-423 board. RS-423 board. Control board.
(8) Control board (ROM board) replacement From the point of the engineers, the control board is referred to by different names: printer control board, main board, ROM board, and main board with ROM (EPROM & mask ROM) . Removal 1. Remove the printing mechanism (Section 4.9.1 (5)). 2. Remove the power supply (Section 4.9.1 (6)). 3. Remove the RS-423 board (Section 4.9.1 (7). 4. Remove the seven screws as shown below, then remove the control board (ROM board).
hInstallation Install the control board (ROM board) in reverse order of removal. Notes: For LA36W printers, be sure to install the grounding metal strip in place. This strip establishes grounding connection between the control board and the power supply. When replacing the ROM, use socket IC1 for an EPROM (program) and socket IC3 for a mask ROM (CG) . The ROM must be mounted with their cut mark oriented inside.
(9) Platen roll assembly replacement Removal 1. Remove the tractor unit (Section 4.9.1 (2)) and covers (Section 4.9.1 (3)). 2. Move the paper select lever as shown below (A). 3. Remove the E-ring. 4. Holding the platen, pull the right platen bearing off the shaft. 5. Move the carriage unit all the way to the right. 6. Move the platen roll all the way to the left (B) and remove the left platen bearing. 7. To remove the platen roll, lift it up (C).
(10) Paper feed motor (LF motor) replacement Removal 1. Remove the printing mechanism (Section 4.9.1 (5)). 2. Remove the motor cable from the cable clamp. 3. Remove the two screws to remove the paper feed motor. Cable clamp Paper feed motor cable Paper feed motor Installation Install the paper feed motor in reverse order of removal. Note: Check that paper feed motor gears are engaged.
(11) Space motor (SP motor) assembly replacement Removal 1. Remove the printing mechanism (Section 4.9.1 (5)). 2. Remove the two screws to remove the space motor. 3. Detach the carriage drive belt from the motor drive pulley, then remove the space motor. 4. Remove the motor cable from the cable clamp. 5. Disconnect the cable connector from the space motor. Motor drive pulley Space motor Cable connector Installation Install the space motor assembly in reverse order of removal.
(12) Sensor T assembly replacement This sensor detects a cut sheet placed on the cut-sheet stand. Removal 1. Remove the tractor unit (Section 4.9.1 (2)) and covers (Section 4.9.1 (3)). 2. Remove the two screws to remove the sensor T assembly while disconnecting the sensor wire cable. Sensor Installation Install the sensor assembly in reverse order of removal.
(13) Carriage unit replacement Removal 1. Remove the printing mechanism (Section 4.9.1 (5)), SP motor (Section 4.9.1(11)), and print head (Section 4.9.1 (14)). 2. Mark the setting positions of the adjustment levers R and L at both sides of the mechanism. (For adjustment lever R, see the figure on the next page.) 3. Loosen the screw to remove the plate spring. 4. Turn adjustment lever L counterclockwise until it contacts the belt (A).
5. Turn the copy control lever so that its notch side is uppermost (A). Then, turn adjustment lever R clockwise until it is stopped (B). 6. Slide the stay shaft slightly to the right (C) and remove the platen bearing. 7. Remove the stay shaft from the frame (D). 8. Remove the cable holder. Stay shaft D Cable holder Carriage unit C A Adjustment lever R B Copy control lever 9. Unhook the spring to free the bracket 10.
(14) Print head and rebbon feed assembly replacement The print head and the ribbon feed assembly are mounted on the carriage unit. The print head is a consumable. Removal Print head Head lock pin Carriage unit 1. Open the front cover. Cover Print head 2. Set the copy control lever to D. 3. Unhook the head lock pin. 4. Lift and remove the print head from the carriage unit. Hook Hook Ribbon feed assembly Ribbon feed assembly 1. Remove the carriage unit from the mechanism (Section 4.9.1 (13)).
(15) Gear assembly replacement The gear assembly transmits power to the paper feed mechanism. It has a mechanism that determines whether power is also transmitted to the push tractor. The assembly includes the LF motor. Removal 1. Remove the printing mechanism (Section 4.9.1(5)). 2. Remove the platen assembly (Section 4.9.1 (9)). 3. Set the paper select lever toward the back of the printer. 4. Loosen the long screw and unhook the three holders from the side frame to remove the gear assembly.
(16) Paper feeder assembly replacement Removal 1. Remove the printing mechanism (Section 4.9.1(5), platen assembly (Section 4.9.1(9)), print head (Section 4.9.1(14)), and gear assembly (Section 4.9.1(15)). 2. Remove the two screws to remove the paper feeder assembly. Paper feeder assembly Sensor assemblies Projections Installation Install the Paper feeder assembly in reverse order of removal. Notes: The paper feeder assembly contains two paper sensor assemblies.
(17) Card guide assembly replacement Removal 1. Remove the platen assembly (Section 4.9.1(9)), print head (Section 4.9.1(14)), and feed roller assembly (Section 4.9.1(16)). 2. Remove the small screw which retains the sensor cable on the card guide. 3. Push the two hooks outwards to remove the card guide from the carriage unit. Hooks Card guide Installation Install the card guide in reverse order of removal. Note: When replacing the card guide, be careful not to damage card guide hooks.
(18) Ribbon shift unit (color kit) replacement Removal 1. Open the front cover, remove the ribbon cartridge, and remove the print head (Section 4.9.1(14)). 2. Release the hook at the right side of the ribbon shift unit to raise the top of the unit. Ribbon shift unit (removed) Hook (right side) Hook (hidden) Hook (front side) (aimed in step 3) 3. Release the other hook at the front side of the ribbon shift unit and pull up the entire unit to remove it from the carriage unit.
4.9.2 Adjustment (1) Print head gap adjustment When replacing the carriage unit or platen, check that the gap between the print head and platen is 0.38 ± 0.03 mm at both ends of the platen. To check the gap along the platen, use a platen gap adjustment gauge and move the carriage to the left and right. To adjust the gap, turn the two levers at the ends of the stay shaft. Procedure 1. Turn off the printer power switch. 2. Remove the covers (Section 4.9.1(3)). 3.
7. Move the carriage unit to the left-end print position (column 1). 8. Turn adjustment lever L at the left end of the stay shaft and adjust it so that the gap is 0.38 ± 0.03 mm. Adjustment lever L Left-side frame 9. Move the carriage unit to the furthest right printing position. 10. Turn adjustment lever R at the right end of the stay shaft and adjust it so that the gap is 0.38 ± 0.03 mm. Paper thickness lever Adjustment lever R Right-side frame 11.
(2) Vertical alignment When replacing the ROM board (printer control board) or the carriage unit, check the vertical alignment by using the diagnostic function on the setup mode menu. It adjusts the vertical alignment of characters printed in opposite directions in bidirectional printing. Adjust for the three print qualities (letter, correspondence, and draft). Procedure 1. Load continuous forms at least 203 mm (8 inches) wide onto the printer to avoid printing on the platen. 2.
3. Check that alignment is correct. 4. If alignment is not correct, press the ® or ¬ button to correct alignment. That is, if forward printing bars come to the left of reverse printing bars, press the ¬ button to make the vertical line straight. If the forward printing bars come to the right of reverse printing bars, press the ® button to make the vertical line straight. 5. Check alignment again. If alignment is not still correct, repeat step 4.
(3) Top-of-forms adjustment (factory use) Top-of-forms (TOF) adjustment in this item is used in the factory to micro-adjust the reference position of the TOF. This mode is not disclosed to users in general. The actual position of the TOF is set by the Top-of-Form adjustment as described in the User Guide (CD-ROM) . Note that this adjustment has an impact on the tear-off position.
4.9.3 Lubrication Lubrication is required only when the printer is overhauled or mechanical components are replaced. Lubrication codes are as follows: 2-GD-D-O Cycle Amount (1 drop) Type (Mobil oil) No. 1. No. Sequential number for the location to be lubricated 2. Type FL: Floil SG: Silicone grease 3. Amount D: S: F: C: 1 drop Several drops Fill the case or oil wick. Cover with thin uniform film 4.
(1) Ribbon drive assembly No.
(2) Color ribbon shift motor (Option) No.
(3) LF gear bearing and continuous/single lever No.
(4) Back cover assembly No.
(5) Paper feed roller shaft No.
(6) Shaft No.
(7) Stay shaft No.
(8) Front and top covers (LA36N) No.
(9) Front and top covers (LA36W) No.
(10)Sheet guide assembly No.
4.10 Diagnostics 4.10.1 Self-test printing Self-test printing produces test pages independent of the computer and the interface between the computer and printer. Use this function to check printer performance after component adjustment or replacement. (1) Starting self-test printing 1. Load continuous forms at least 203 mm (8 inches) wide onto the printer to avoid printing on the platen. 2.
(2) Checking printer performance The self-test printing pattern includes the following: • Header (If started from Set-Up mode) • Help menu briefly explaining how to use buttons (If started from Set-Up mode) • Repeated printing of 80 characters per line (ASCII Hex 21 to 7E and A0 to FE) With a color printer (color kit installed printer), 80 characters per line are printed repeatedly using seven colors: black, magenta, cyan, violet, yellow, orange, and green.
4.10.2 Hex dump In hex dump, the printer prints data and commands in 2-digit hexadecimal code. The interface operation is the same as online in Normal mode. It enables the checking of character sequences the computer sends to the printer as commands which are interpreted but not printed in regular mode. One line contains 16 two-digit hexadecimal codes and corresponding ASCII characters. (1) Starting hex dump printing 1.
4.10.3 Control panel maintenance functions initiated when power goes on The printer provides several maintenance functions initiated by holding buttons down when power is turned on. Continue pressing until the printer beeps. Table 4.
CHAPTER 5 PRINCIPLES OF OPERATION 5.1 Overview This section explains the principles of LA36N and LA36W operation. A microprocessor controls the following basic functions: Interface Carriage drive Print head drive Paper feed drive Ribbon shift drive (color option) Figure 5.1 gives the function sequence: Carriage drive Print head drive Paper feed drive Figure 5.
5.2 Mechanical Operation 5.2.1 Print head drive The print head consists of 24 wires in six columns (see Figure 5.2). The print head has 24 electromagnets that drive armatures. When not printing, the armature is set at the stopper by the coil spring connected to the wire. During printing, the coil for the dot to be printed is excited, the armature is drawn in the direction indicated by the arrow, and the armature pushes the wire in the same direction.
5.2.2 Carriage drive The print head carriage is moved by the 4-phase space motor (SP motor in the recommended spare parts) in the left corner of the frame. The drive pulley on the space motor shaft is connected to the tension pulley at the right corner of the frame through the timing belt. The print head carriage is on the stay shaft parallel to the platen and the front stay (rack rail) fixed on the front of the frame so that it moves in parallel with the platen axis.
5.2.3 Ribbon feed Ribbon is fed by the ribbon feeder on the bottom of the print head carriage. This mechanism links carriage movement to ribbon movement so that the ribbon moves in one direction, regardless of whether the carriage moves left or right. The ribbon feeder receives power from the front stay (rack rail) through the RF gear. Power is transmitted to gear C, a planet gear. Gear C engages one of two gears, depending on carriage movement.
5.2.4 Paper feed Paper is fed by the 4-phase paper feed motor (LF motor) on the left side of the frame which rotates the platen and operates the tractor unit. The LF motor gear transmits power to the platen gear through idle gears A and B. When the tractor unit is installed at the rear of the printer for use as a push tractor, the paper select lever is set toward the back of the printer (continuous forms side).
(1) Continuous forms feeding A pair of left and right pin belt tractors on the square tractor shaft feed continuous forms. The tractor is installed above the printer as a pull tractor or on the back as a push tractor. a. Push tractor Continuous forms, fed by pin belt tractors, advance along the card guide on the carriage, then move up over the platen. After passing the card guide, forms are pinched by the platen and bail rollers to remove slack.
b. Pull tractor Continuous forms fed from the bottom slot, advance along the card guide on the carriage, then, move up over the platen. Platen Card guide Platen Continuous forms Card guide Figure 5.
(2) Cut-sheet feeding As the platen rotates, a cut sheet is pinched between the feed roller and platen and fed forward. To pass the printing section, the sheet is guided by the card guide and fed further between the bail roller and the platen. Bail roller (*) * For the bail roller, its support mechanism differs with LA36N and LA36W. This is for LA36N. Platen Card guide Feed roller Cut sheet Card guide Platen Figure 5.
(3) Paper selection Since continuous forms and cut sheets are fed differently, the paper feed mechanism is based on the type of paper. When the paper select lever is switched from the continuous forms location (back) to the cut-sheet location (front) as shown below, gear C slides off the tractor gear and stops transmitting rotation to the continuous forms feed tractor. At the same time, the paper select lever operates the link mechanism then activates the microswitch to indicate the cut-sheet select status.
(4) Autoloading In autoloading, paper is loaded up to a specified position without turning the platen knob. Once the FF/Load button on the control panel is pressed, the carriage moves to the center. The LF motor then drives the paper feed mechanism to feed paper. Paper is guided by the card guide on the carriage and pinched between the bail rollers and the platen. Paper is always loaded up to the specified position which is set separately for cut sheets and continuous forms.
(5) Paper end detection a. Cut sheet The presence of paper and paper near end position are detected by sensor A, an interrupt photosensor in the sensor T assembly. When there is paper, the paper shields the sensor light path. The top edge of paper is detected by sensor B, a reflection photosensor on the card guide. When paper is not loaded, the light emitted from the photosensor is not reflected because the platen is black. When paper is loaded, the light is reflected from paper.
b. Continuous forms fed via push tractor The top of continuous forms is detected by sensor B (detailed in Figure 5.11) and by feeler 1 linked to sensor C, an interrupt sensor. The feeler 1's movement is transmitted to the sensor shield lever. When there is paper, the paper pushes down feeler 1 and the shield lever opens the sensor light path. Paper end is detected by feeler 2 on the tractor unit. It is approximate 80 mm from the print position.
c. Continuous forms fed via pull tractor from the bottom slot Paper end is detected by feeler 3 linked to sensor C (detailed in Figure 5.12). It is approximate 35 mm from the print position. d. Continuous forms fed via pull tractor from the rear side Paper end is detected by feeler 3 linked to sensor C. Continuous forms Pull tractor Feeler 1 Feeler 3 Figure 5.
5.2.5 Print head gap control (paper thickness adjustment) The print head is mounted on the carriage which is guided by the stay shaft. The stay shaft is eccentric because it has adjustment levers R and L, on each side, that engage eccentrically with side frames. Turning levers adjusts the parallelism of the stay shaft to the platen, thus making the print head gap equal between right end and left end.
5.2.6 Color ribbon shift motor (option) The stepping motor turns the eccentric cam to move the ribbon shift lever, which lifts the color ribbon cartridge to the location of a selected color (one of the four colors). If a monochrome ribbon cartridge is loaded, the color printer works as a monochrome printer. Color ribbon cartridge Ribbon shift lever Stepping motor Eccentric cam Figure 5.
5.2.7 Option detection mechanism This printer has the mechanism that automatically detects whether the tractor unit is installed as a push tractor or a pull tractor. Installing the tractor unit at the rear of the printer pushes down the feeler and raises shield plate A as shown below. The photosensor on the bottom of the carriage detects this condition and determines that the push tractor is mounted. Platen Feeler Up for push tractor Carriage unit Shield plate A Figure 5.
5.3 Electrical Operation This section briefly explains circuits and how they operate. 5.3.1 System configuration The Fujitsu MB90706 MPU receives data and commands from the host computer and controls the printing mechanism (Figures 5.17 and 5.18). Printer Printer control board (Main board) Control panel MB90706 Host computer Sensors Interface controller (Centronics) Printing mechanism MBCU20050 Driver circuit Interface controller (RS-423) Power supply unit Figure 5.
Sensors: Paper select Paper end Power supply Color ribbon shift motor Sensors: Left end CNHD3 CNHD1 AC input 100 ~ 200 VAC or 220 ~ 240 VAC 100 V: PW34AA 200 V: PW34 BA CNHD2 CNPW INFCEN CNSEN Print head Control board (main board) RC98CB Centronics RS-423 CNLF CNSP RS423 CN423 RS95AA CNOP RO93BF Paper feed Carriage motor motor Control panel Figure 5.
The LA36N/LA36W controller (Figure 5.17) consists of an printed circuit board, called the printer control board or the main board with ROM. The MPU controls operation under control of programs in ROM. (1) Printer control board (ROM board) The printer control board governs the interface, memory, and mechanism. It is also called ROM board. The name on the Recommended Spare Parts List is “main board with ROM”. Interface: The LA36N/LA36W provides two types of interface –– Centronics parallel and RS-423 serial.
5-20 OPLSI LSI1 Buzzer Control panel Push buttons and LEDs Interface +34V HDLSI MPU Print head Driver Printing mechanism Ribbon shift motor (option) Driver D-RAM (Data, etc.) Figure 5.
The MPU (MB90706) has the following main functions: Timing controller Dynamic RAM controller Address decoder Interface controller Motor controller ADDRESS CPU F2MC-16 X0 X1 RST *FLTO *RC RCD *DTR *TD *RTD *RD *DSR *CTS *CD CLK Clock control circuit Space motor control circuit DATA01~08 EXPRM INPRM DSTB *ACK BUSY *FAULT SLCT *AFXT *SLCTIN DATA Centronics interface control circuit RS-232C interface control circuit *SDIN Paper feed motor control circuit SPM00~03 SPI01~02 LFM00~03 LFI01~02 Color r
The HDLSI(LSI 2: MBCU20050) has the following main functions: Head pin magnet drive controller Output port TIMER1 A01~A05 *EXIOCS *IOWRL *IOWRH *IORD CLK Address decoder Division circuit Print head driver and controller PD01~24 Flyback controller FLYBK01~06 D00~D15 I/O port OUT00~07 IN00~IN04 HDALM00~06 SPALMS SPALML LFALMS LFALML Alarm detection circuit *POWST *DVALM Figure 5.
5.3.2 Main controller The main controller circuit of the printer –– the MB90706 MPU –– has a bus connected to 4M-bit ROM, two16M-bit ROMs, 128K word x 16-bit RAM, and a control LSI. Firmware functions are built into the 4M-bit ROM and one of the two 16M-bit ROMs is reserved for optional CG data. 000000 I/O and work RAM 5FFFFF 600000 ROM Program ROM ROM Resident CG ROM Resident CG (optional) RAM Buffer RAM A00000 C00000 E00000 FFFFFF Figure 5.
Table 5.1 shows the memory address map. Table 5.1 Memory address map Address area (hex) Size (bytes) 000000 ~ 0000BF 192 0000C0 ~ 0000FF 64 I/O area (external) 000100 ~ 00037F 640 Work RAM (direct addressing) 000380 ~ 5FFFFF 5.
5.3.3 Interface control (1) Centronics parallel interface Received data DATA1 to DATA8 is latched to the internal MPU register just after the falling edge of the Strobe signal *DSTB. The BUSY signal goes high. The MPU recognizes that data has been received and stores the information in the receive buffer or processes it immediately. After the operation finishes, the MPU issues the *ACK signal and the BUSY signal goes low. *DSTB DATA 1 to DATA 8 BUSY *ACK Figure 5.
(2) RS-423 serial interface The serial interface control circuit is basically the same as the Centronics circuit, except that it has a serialparallel converter. Serial data sent to the interface circuit input terminal is converted to TTL by the receiver IC and applied to the MPU (MB90706), which converts serial data to parallel. The MPU recognizes that data has been received and stores the information in the receive buffer or processes it immediately.
5.3.4 Carriage motor control The 4-phase carriage motor, is driven by a constant current chopper drive circuit and six control signals: SPM0: SPM1: SPM2: SPM3: SPI1, 2: This signal drives phase A of the carriage motor. This signal drives phase B of the carriage motor. This signal drives phase C of the carriage motor. This signal drives phase D of the carriage motor. These signals switch the carriage motor phase current. Four current levels can be selected for high speed, low speed, and stop.
The MPU receives phase excitation data for the stepping motor and sends data to turn the motor drive HIC on or off. Data is set to high for a phase to be excited. Motor rotation is controlled by sequentially changing the excitation of the four phases. Slew control is applied when motor rotation starts or stops: Start: Stop: Gradual acceleration. The excitation period gradually is made shorter. Gradual deceleration. The excitation period gradually is made longer.
The LA36N/LA36W printer has several spacing speeds, and drives the carriage either by 1/2 phase or 2-phase excitation, based on speed (Figure 5.27). Draft (High-speed) 360 2-phase excitation Speed (10 cpi) cps NLQ (*2) 225 (*1) (*1) Letter quality 1/2-phase excitation 112.5 Time *1 Slewing *2 Near-letter-quality, also called correspondence Figure 5.
Figures 5.28 and 5.29 show 1/2-phase and 2-phase excitation. Idle Operating SPI1, 2 SPM0 (φA) SPM1 (φB) SPM2 (φC) SPM3 (φD) Drive phase A A B B C C D D A A B B C C D D A A B C D A B C D A B Figure 5.28 Carriage drive 1/2-phase excitation at low speed SPI1, 2 SPM0 (φA) SPM1 (φB) SPM2 (φC) SPM3 (φD) Drive phase D D A B C D A B C D A B C D A B C D A B C D A B C A B C D A B C D A B C D A B C D A B C D A B C D Figure 5.
5.3.5 Print head control Operation from reading print data to driving the pin magnet is as follows (Figure 5.30): 1. Print data is read from line buffer RAM. 2. Data is sent to the HDLSI(MBCU20050), being set to high for dots to be printed. 3. Excitation and flyback absorption timers are in the HDLSI. 4. Print data and excitation time are ANDed and, the result is output by the HDLSI, then the print head drive transistor is turned on.
If +34 volts goes below the prescribed level during printing, the printer splits one line of printing into three-pass printing to limit the number of pin magnets excited at the same time, thus reducing the power load. If low voltage continues even in three-pass printing, an alarm is generated. Figure 5.31 shows the print timing and waveforms of the head pin magnet drive current.
5.3.6 Paper feed control The 4-phase paper feed motor is driven by four signals: LFM0: LFM1: LFM2: LFM3: LFI1, 2: This signal drives phase A of the paper feed motor. This signal drives phase B of the paper feed motor. This signal drives phase C of the paper feed motor. This signal drives phase D of the paper feed motor. These signal switch the paper-feed motor phase current. Four current levels can be selected for high speed, and stop.
Unlike carriage spacing, paper is fed at only one speed (Figure 5.33), and driving is always done using 2-phase excitation (Figure 5.34). Paper feed speed 5.6 ips Time Figure 5.33 Paper feed speed Idle Operating LFI1, 2 LFM0 (φA) LFM1 (φB) LFM2 (φC) LFM3 (φD) Figure 5.
5.3.7 Ribbon shift control The 4-phase ribbon shift motor is driven by four signals: CLM0: CLM1: CLM2: CLM3: This signal drives phase A of the ribbon shift motor. This signal drives phase B of the ribbon shift motor. This signal drives phase C of the ribbon shift motor. This signal drives phase D of the ribbon shift motor. Phase switching is controlled by the timer in the MPU used to determine the phase drive period (Figure 5.35). AB BC DA CD Figure 5.
Unlike carriage spacing, ribbon shifting is only at one speed (Figure 5.36), and driving is always done using 1/2phase excitation (Figure 5.37). Ribbon shift speed Time Figure 5.36 Ribbon shift speed Ribbon shift stop Ribbon shift in progress Ribbon shift stop CLM0 (φA) CLM1 (φB) CLM2 (φC) CLM3 (φD) Figure 5.
5.3.8 Fire check control Figure 5.38 shows fire check circuits. The fire check protects the carriage motor (SP motor), paper feed motor (LF motor), and color ribbon shift motor (option) from burning out if the control or drive circuit malfunctions. Two types of fire check detections are used –– short-mode detection for an abnormal large current and longmode detection for abnormal forcible excitation. (1) Short-mode detection a.
d. HDLSI An internal timer is started by HDLSI after the alarm signal is received and the PWSTOP signal is output to the power supply after counting up. If the PWSTOP signal is output, the power supply (+34 V and +5 V circuits) is turned off to keep the SP and LF motors from burning out.
5.3.9 Control panel control The control panel has 16 LEDs, 7 push-button switches, a buzzer, and an LSI (MB623829) to control them. The switch contact signals and LED drive signals are transmitted between the main board and the control panel through a flat cable. An LED drive signal is issued from the main board to the LSI as serial data which the LSI converts into parallel data.
5.3.10 Power Supply There are two types of power supplies: 100-120 VAC input: 29-33026-01 (PW31AA) 220-240 VAC input: 29-33027-01 (PW31BA) The power supply output voltage is +5 V for the logic circuits and +34 V for the printer mechanism drivers (Figure 5.41). AC input from the power connector via the power-on switch is converted to DC by rectifier and smoothing circuits. The amount of surge current is limited by the surge current prevention circuit.
5-41 AC inlet Power supply unit Fuse SW Noise filter Rectifier circuit B Smoothing circuit Surge current prevention circuit Main switching circuit C Figure 5.
(3) Main voltage regulation switching (Figure 5.41 C) Smoothed DC voltage is converted to high-frequency on/off voltage by changing the frequency and duty of the on/off voltage pulse (Table 5.2). Table 5.2 Voltage regulation switching control Voltage +5 V +34 V Switching control Self-activated flyback converter Regulation control Frequency change (duty also changed) Frequency 20 kHz to 250 kHz (4) Protection a. Primary circuit protection A fuse is equipped between the power inlet and the power switch.
b. Secondary circuit protection Overcurrent protection (OCP) If a short circuit occurs at the load, overcurrent protection starts for the current range below (Table 5.3) to prevent the current from increasing, thus lowering output voltage. Table 5.3 Overcurrent protection Voltage Overcurrent detection Protection +5 V 1.0 A or more Foldback +34 V 4.
(5) External signal The power supply receives the PWSTOP signal (Power Stop signal, connector pin No. 2) from other printer components that enables the printer controller to turn off +5 V and +34 V outputs even if problem that can result in power failure occurs outside the power supply. When power is turned on, the PWSTOP signal is kept low and +5 V and +34 V output go to the prescribed values. When the PWSTOP signal is made to go high due to a failure, +5 V and +34 V are cut off (Figure 5.42).
5.4 Firmware Overview LA36N/LA36W firmware, stored in ROM, is separated into three independent software groups, –– interpreter control, print control, and base control (Figure 5.43). Epson ESC/P2 IBM Proprinter X24E/XL24E Digital PPL2 3 2 Host interface control, control panel control Level 1 interrupt Interpreter control group 1 Print information Print control group Level 2 interrupt Print request, paper feed request, etc.
CHAPTER 6 RECOMMENDED SPARE PARTS The following table lists parts and product numbers to be used when ordering spare parts. It also indicates the sections that explain the replacement. No FJ PARTS NO. PARTS DESC. LA36 N W Section tobe referred to Remarks 1 CA02744-J301 Main Board with ROM X X 4.9.1 (8) 2 CA20160-B30X Main Board X X 4.9.1 (8) 3 CA20160-B65X OP Board X X 4.9.1 (4) Control panel 4 CA20160-B70X RS423 Board X X 4.9.
No FJ PARTS NO. PARTS DESC. LA36 N W Section tobe referred to Remarks 23 CA02312-G375 Card Guide Assy X X (4.9.1 (17)) Plastic print guide 24 CA02312-Y07003 Side Cover X X 4.9.
LA36 SPARE PARTS CROSS REFERENCE LIST Option Used-on LA36N/W LA36N LA36W LA36W LA36N LA36N/W LA36N/W LA36W LA36W LA36N LA36N LA36W LA36W LA36N/W LA36N/W LA36N/W LA36N/W LA36W LA36N LA36W LA36N LA36N/W LA36N/W LA36N/W LA36N/W LA36N/W LA36N/W LA36N/W LA36N LA36N LA36N LA36N Compaq Classic Digital Classic Spare Compaq Description Spare P / N P/N 158007-001 158029-001 158036-001 158032-001 158025-001 158023-001 158022-001 158037-001 158033-001 158030-001 158026-001 155089-001 155090-001 155081-001 158017-001 1
LA36N LA36N LA36N LA36N LA36W LA36W LA36W LA36W LA36N/W LA36W LA36N/W LA36N/W LA36N/W LA36N/W LA36W LA36N LA36N/W LA36N/W LA36N/W LA36N/W 155093-001 155099-001 155095-001 155098-001 155086-001 155088-001 155092-001 155087-001 155080-001 155091-001 158008-001 158010-001 158011-001 158014-001 158034-001 158027-001 158012-001 158013-001 158020-001 158021-001 29-34626-C1 29-34632-01 29-34628-01 29-34631-01 29-34619-01 29-34621-C1 29-34625-01 29-34620-01 29-34613-C1 29-34624-01 29-33024-01 29-33026-01 29-33027
