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Service Guide ML390/ML391Turbo
Chapter 0 About This Manual
ML390 Turbo // ML391 Turbo Dot Matrix Printers
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 ML390/ML391Turbo
0 About This Manual Front Cover Copyright / About Information 1 Configuration 1.1. Standard Printer Configuration 1.2 Options 2 Theory of Operation ....2.1.01 Summary ....2.1.02 Microprocessor and the Peripheral Circuit ........Printer Block Diagram (Figure 2-1) ........Program ROM ........RAM (MSM51C464A-80RS) ........EEPROM ........Large Scale Integrated Chip (LSI) ....2.1.03 Initialization ....2.1.04 Parallel Interface Control ....2.1.05 Print Control ........Print Compensation Control ....2.1.06 Space Motor / Line Feed Motor Control ....2.1.07 Operation Panel ....2.1.08 Alarm Circuit ....2.1.09 Power Supply Circuit 2.2.01 Printhead Mechanism and Operation ....2.2.02 Spacing Operation ....2.2.03 Head Gap Adjusting ....2.2.04 Ribbon Drive ....2.2.05 Paper Feed Operation ........(1) Cut Sheet and Continuous Forms Switching Mechanism ........(2) Cut-sheet feeder operation ........(3) Continuous Forms Operation (Rear) ........(4) Push and pull tractor mechanism (Option) ........(5) Pull tractor mechanism (option) ........(6) Bottom Push Feed Operation (Option) ........(7) Paper Clamp Mechanism ....2.2.06 Paper Detection Mechanism ....2.2.07 Automatic Sheet Feed ....2.2.08 Paper Park Function (Continuous Forms) 3 Assembly/Disassembly ASSEMBLY/DISASSEMBLY ....3.1 Precaution for Parts Replacement ....3.2 Service Tools 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
Table of Contents ....3.3 Disassembly/Reassembly Procedure ............How to Change Parts ........3.3.01 Printhead ........3.3.02 Ribbon Protector ........3.3.03 Pull-up Roller Assy ........3.3.04 Upper Cover Assy, Access Cover Assy and Sheet Guide Assy ........3.3.05 Gear Case Assy ........3.3.06 PC Connector ........3.3.07 Space Motor, Guide Roller Assy ........3.3.08 Space Rack ........3.3.09 Carriage Cable ........3.3.10 Backup Roller Holder Assy ........3.3.11 Platen Assy ........3.3.12 Driver Board (SRXD) ........3.3.13 LF Motor ........3.3.14 Operation Panel PCB (LEOP) ........3.3.15 Control/Power Supply Board (SRXC) ........3.3.16 Transformer Assy ........3.3.17 Change Lever and Gears ........3.3.18 Carriage Shaft ........3.3.19 Paper Pan ........3.3.20 Rear Tractor Assy ........3.3.21 Rear Pressure Assy ........3.3.22 Switch Lever 4 Adjustments 4. ADJUSTMENT ....4-1-1 Gap between the platen and the printhead ....4-1-2 Measure variation of gap when range is changed. 4-2 Gap between the platen and the paper pan 4-3 Gap between the platen and the pressure roller ....4-4-1 Rotation of the push tractor ....4-4-2 Backlash between gears ....4-5-1 Ribbon feed ....4-5-2 Running load to spacing mechanism ....4-6 Engagement of the double gear and the LF motor idle gear of the Platen 5 Cleaning and Lubrication 5.1 Cleaning 5.2 Lubrication ....(1) Cleaning time ....(2) Lubricant ....(3) Amount of lubricant ....(4) Areas to Avoid
Page 38 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
Table of Contents ........(5) Lubrication points -- 1. Ribbon feed gear Assy. ........2. Space rack ........3. Platen Assy. ........4. Tractor driving mechanism ........5. Tractor drive shaft ........6. Pressure roller ........7. Pull up roller Assy. ........8. Main chassis Assy. ........9. Carriage Assy. 6 Troubleshooting and Repair 6.1 Items to Check Before Repair 6.2 Troubleshooting Table 6.3 Lamp Display 6.4 Connection Circuit Check for Printhead and SP/LF Motor ........(2) Line Feed Motor ........(3) Space Motor 6.5 Troubleshooting Flow Charts ........2 No Spacing Operation (The Alarm LED Blinks) ........3 Homing does not end normally ........4 Paper jam while paper insertion ........5 Smearing/Missing Dots ........6 Faint or dark print ........7 Ribbon feed trouble ........8 Line feed trouble ........9 Malfunction of switch on operation panel ........10 Data receiving failure A PCB Layout APPENDIX A: PCB LAYOUT B Parts Listing SPARE PARTS LIST ....Upper Cover Assembly (Figure 11-1) ....Printer General Assembly (Figure 11-2) ....Printer Unit (Figure 11-3 ) [1 of 2] ....Printer Unit (Figure 11-3 ) [2 of 2] ....Carriage Option Assembly (Figure 11-4) ....Option Spare Parts (Figure 11-5) C RS-232C Serial Interface Board APPENDIX C: RS-232C SERIAL INTERFACE BOARD C2. Operation Description ........C2.2.01 Operation at Power On ........C2.2.02 RS-232C Interface ....C2.3 Communication Procedure Flowchart ........C2.3.02 Mode B (Figure C-2-3) C3. Troubleshooting Flowcharts
Page 78 79 80 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
Table of Contents ....C3.3 Local Test ........C3.3.1.2 Function
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Service Guide ML390/ML391Turbo
Chapter 0 About This Manual
Disclaimer This document may not be reproduced without the written permission of Okidata Training and Publications. 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. Copyright / About Information 1996 by Okidata. All rights reserved. First Release P/N 59274601 November, 1996 Written by: OKI Data Corporation 11-22, Shibaura 4-chome, Minato-ku, Tokyo 108, Japan Tel: +81 (Japan)-3 (Tokyo)-5445-6159 Fax: +81-3-5445-6188 Revised by Okidata Training and Publications Contact Please address any comments on this publication to: OKIDATA Training and Publications 532 Fellowship Road Mount Laurel, NJ 08054-3499 Okilink Login Name: Technical Training Internet Web Site: okidata.com Copyright Listing OKIDATA is a registered trademark of Oki America, Inc. OKIDATA est une marque déposée de Oki America, Inc. Centronics is a registered trademark of Centronics Data 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)
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Service Guide ML390/ML391Turbo
Chapter 1 Configuration
1.1. Standard Printer Configuration This printer consists of the following assemblies:
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Service Guide ML390/ML391Turbo
Chapter 1 Configuration
1.2 Options (1) Cut Sheet Feeder Unit (CSF) Single-Bin Cut Sheet Feeder
(2) Pull-tractor Assembly
(3) Bottom Push Tractor Unit
(4) Roll Paper Stand (Narrow only)
(5) Serial Interface
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
2.1.01 Summary Figure 2-1 shows the block diagram of the printer. The control board is made up of the microprocessors, peripheral circuits, drive circuits, sensors and interface connectors. The power to the control board is supplied by the power board through the connector cord. The power to other electrical parts is also distributed through the connectors within the control board.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
2.1.02 Microprocessor and the Peripheral Circuit Microprocessor (Q7: 67X640) This processor is a CMOS single-chip computer with integrated peripheral device functions and a 16 bit MPU core, all OKI original architecture. The processor has a 20 bit address bus and a 16 bit data bus. It is capable of accessing up to 1M word program memory and 1M bytes of data memory. The following characteristics are also provided:
Built-in type data memory of 512 bytes 8-bit 4-channel A/D converter ¥ 1 16-bit automatic reload timer ¥ 2 8-bit serial port ¥ 2 8-bit parallel port ¥ 3 (bitwise I/O specification available)
And others. The function of this microprocessor is to provide a central mechanism for the entire printer by executing the control program through the LSI and driver circuits. 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)
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
Printer Block Diagram (Figure 2-1)
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
Program ROM This is a 256 ¥ 16 bits (4M bit) [MAX] EPROM with the control program for the printer stored. The MPU executes instructions under this program. The program ROM is assigned to the program memory area of the MPU and is fetched by the PSEN signal of the MPU. The following shows the operation of the memory access.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
RAM (MSM51C464A-80RS) The RAM is CMOS dynamic RAM with (64K ¥ 4-bit) ¥ 2 configuration, and used as buffers (such as receiving buffer, printing buffer, DLL buffer and working buffer). The following shows the examples of the memory access operation.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
EEPROM The EEPROM is a CMOS serial I/O type memory which is capable of electrically erasing and writing 1,024 bits. The EEPROM contains menu data. The following shows the memory access operation.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
Large Scale Integrated Chip (LSI) This LSI detects and controls the SP motor speeds by monitoring the two phase sensor signals obtained from the DC motors and modifying the excitation phases as appropriate. This LSI is connected in multiplex to the MPU.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
2.1.03 Initialization This printer is initialized when the power is turned on or when the I-PRIME-N signal is input from the host side via the parallel interface. For the initialize operation, the RST-N signal is first output from the reset circuit to reset the MPUs and LSIs. When resetting ends, the program starts and the LSIs are reset by MPU via LSIRST-N. Reset operation by I-PRIME starts program to initialize, but does not reset the MPU. The program here sets the mode of the LSI including the MPU, checks the memories (ROMs and RAMs), then carries out carriage homing, and determines the LF motor phase. Finally, the program establishes the interface signals (P-I/F: ACK-P signal sending, and S-I/F: BUSY-N signal off) and lights the SELECT lamp to inform the ready state for receiving to the host side and ends the initialize operation.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
2.1.04 Parallel Interface Control The parallel data input from the host to the interfaced LSI is latched to its internal register at the falling edge of the STROBE-N signal. At the same time, the LSI sets the BUSY signal to the high level to inform the host that the data is being processed, and outputs the RXD signal to inform the MPU of data reception. The data is read upon receiving the RD-N signal from the MPU. When the data processing ends, the BUSY signal is set to off and the ACK-N signal in sent to request the next data. When reception is impossible because the buffer is full, the BUSY signal is sent to request stopping of data transmission.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
2.1.05 Print Control Print data is transmitted as parallel data (HEAD1~HEAD24) from LSI to print head. LSI generates print timing and drive time.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
Print Compensation Control The print compensation can be made as shown below: (a) Voltage compensation (See 2.1.8 "Alarm Circuit.") "Alarm Circuit.")
(b) Temperature compensation (See 2.1.8 (c) Pin stroke compensation
(d) Simultaneous Compensation of the number of impact pins The LSI is provided with the compensation table for each pin to make necessary compensation.
Print Mode Compensation According to the thickness of the printing medium, the print mode is compensated as shown in the table below:
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
2.1.06 Space Motor / Line Feed Motor Control Space Motor Control The SP motor driver (HA13412) drives the three-phase brushless motor based on the phase signal (SPU, SPV and SPW) and the speed instruction data from the LSI. The MPU can identify the current speed of the space motor by measuring through the LSI the pulse length of the output (øA, øB) of the slit encoder included in the space motor. By comparing the target speed for each print mode with the actual current speed to change the speed instruction data, the motor speed is accelerated or decelerated to maintain the specified speed for each print mode.
Encoder Disk In the operation of the spacing motor, the PHASE-A and PHASE-B signals are generated when the encoder disk interrupts the photo sensor. The LSI divides these edge pulse signals in accordance with the print pitch, and sends the IPT signal to provide dot-on timing and carriage position detection timing.
Line Feed Motor Control The Line Feed motor driver (MTD2005F) drives the Line Feed motor in two-phase or 1-2 phase bipolar, based on the phase changeover data and the output current data from the LSI. The data from the LSI is processed by a specific register contained in the LF motor driver to measure the overdrive time and to change the phase.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
2.1.07 Operation Panel The clock synchronization OPCLK of LSI is used to input the switch data and output the LED data through the operation panel control LSI (IC1: BU5148S).
A 2-byte (15 bits + 1 even parity bit) command (OPTXD) is transmitted to the LSI (BU5148S) in synchronization with the OPCLK signal. The LSI decodes this command and when it is found to be legal, returns a 2-byte command response back to the LSI which includes data on Switch information, LED status, receive command ACK/NAK and 1 odd parity bit. Any transmission errors found cause the command to be reissued after the transmission of the OPCLR-N signal.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
2.1.08 Alarm Circuit Head Drive Time Alarm Circuit This circuit monitors the drive time using the HDALM signal interlocked with the overdrive signal of each drive circuit. If the drive time of any drive circuit exceeds the specified time, the drive fault alarm circuit sends an ALARM-N signal to turn on the SCR (SO). This cause the secondary coil (40V) of the transformer to be short-circuited, causing an overcurrent to flow through the primary coil and making the AC fuse (transformer ASS) open. Alarm Processing When DC Power is Low + 40V is converted into the POWLEV signal (0V to +5V) by R531 and R532 and input into the A/D port of the MPU to control the drive time and the print speed (pass number) of the head.
Head Drive Time The head drive time is lengthened to compensate for the amount of voltage drop by monitoring the POWLEV signal once every 500 m sec. to control and maintain the impact necessary for each printing pin at the fixed value. Print Speed
Head Overheat Alarm The voltage of the output TSD signal of the thermistors, one of which is contained in the print head and the other in the print head driver, is monitored by the CPU/AD port to control the voltage.
When the temperature is between a°C and 119°C, the mode switches sequentially to higher level. When the temperature falls below ß°C, the mode switches to lower level. When the temperature exceeds 119°C, printing will stop. When temperature gradient is steep, higher mode shall be specified directly.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
2.1.09 Power Supply Circuit This power supply circuit supplies the +5VDC, +8VDC, +40VDC, 10VAC.
The uses of output voltages and signals are described below. Voltage/signal +5V +8V + 40V AC 10V Use Logic IC/LED drive voltage Serial interface line voltage and SP motor driver Printhead, LF motor drive voltage, SP motor drive voltage Option board
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
2.2.01 Printhead Mechanism and Operation Refer to Figure 2-2 (shown below) The printhead is a spring charged 24-pin driving head using a permanent magnet. It is attached to the carriage, which moves in parallel with the platen. Electrically, this unit is connected to the control circuits through the control board.
Figure 2-2 Arrangement of the head pins, View from the tip of the printhead
(1) Printhead Configuration The printhead is composed of the following parts: (a) Wire guide (b) Spring assembly (Wire, Armature, Spring, Yoke, Spacer) (c) Magnet assembly (Magnet, core, coil, Yoke) (d) Printed circuit board (e) Fin (2) Operation of Printhead Refer to Figure 2-3 (shown below) (a) When the printhead is idle, the armature is attracted by a permanent magnet and the spring fixing the armature is compressed. The print wires fixed to each armature are thus concealed under the wire guide. (b) When a signal for a character to be printed is detected, a current flows through the coil. When the coil is activated, the magnetic flux (caused by the permanent magnet between the armature and the core) is canceled to eliminate the attraction force. The armature is driven in the direction of the platen by the force of the armature spring. The print wire fixed to the armature
protrudes from the tip of the wire guide, strikes the paper through the ribbon and prints a dot on the paper. (c) After the character has been printed, the armature is magnetically attracted again and the print wires are again concealed under the wire guide. A thermistor in the printhead prevents burning caused by over-heating of the coil during extended continuous bi-directional printing. When the temperature of the coil exceeds a pre-determined limit (about 119°C) the control circuit detects a thermistor signal. Printing will then be intermittent or stop completely until the coil temperature falls below the limit value.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
2.2.02 Spacing Operation Refer to Figure 2-4 (shown below). The spacing mechanism consists of a carriage shaft mounted in parallel with the platen, and a carriage frame that moves along the shaft. It is driven by a DC motor mounted on the bottom of the carriage frame. Items included in the spacing mechanism are as follows: (a) DC motor with motor gear (b) Carriage frame (stationary yoke and motor driver board included) (c) Carriage shaft (d) Space rack (e) Sensor (f) Encoder disk (1) Spacing Operation The carriage frame, on which the printhead and space motor are mounted, moves along the carriage shaft in parallel with the platen. When the spacing motor rotates counterclockwise, the driving force is transmitted to the motor gear. As the motor gear rotates, the carriage moves from left to right. Mechanically, it is designed in such a way that for every revolution of the DC motor, the carriage frame moves 0.8 inch (20.32 mm). At the same time the encoder disk rotates together with the motor and passes the sensor. The position of the carriage frame can be determined by counting the inter-rupts detected by the sensor. In the same way, the rotation of the space motor can be recognized and controlled by measuring the cycle of interrupts detected by the sensor.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
2.2.03 Head Gap Adjusting Refer to Figure 2-5 (shown below). The head gap adjusting lever moves back and forth to tilt the carriage frame, altering the gap between the printhead and the platen. The adjusting screw, which is connected to the adjusting gear rotates when the adjusting lever is moved creating a fine gap adjustment. If the adjusting gear is pushed down, the adjusting screw can be turned with a screw driver to change the coarse gap adjustment. When the adjusting lever is set to range ¡ ~ the contact which is attached to the under side of the carriage cover will connect with the contact of the space motor PC board. The printer will reduce the printing speed automatically to ensure that adequate printing pressure is maintained for multipart paper. And, the adjusting cam adjusts the headgap toward left and right side in accordance with the guide rail up and down as a position of the left end of it.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
2.2.04 Ribbon Drive Refer to Figure 2-6 (shown below). The ribbon driver mechanism moves the ribbon in synchronization with the space motor operation. The ribbon drive mechanism consist of the following items: (a) Ribbon drive gear assembly (b) Ribbon gear (space motor) (c) Ribbon cartridge (1) Ribbon Cartridge An endless ribbon with a single direction feed is used. Ink is supplied from an ink tank, which is built in to the ribbon cartridge. (2) Ribbon Feed Operation When the space motor is activated, the ribbon gear rotates. The rotation is transmit-ted via the ribbon drive gear assembly to the drive gear in the ribbon cartridge, thus moving the ribbon. The feed direction of the ribbon is maintained by switching the rotational direction of the gears in the ribbon drive gear assembly. This ensures ribbon movement when bidirectional printing is used.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
2.2.05 Paper Feed Operation Feeding of the paper is performed by turning the platen and the pin tractor, which is driven by the Line Feed Pulse Motor. The paper feed mechanism is made up of the items listed below. (a) Pulse motor with gears (b) Decelerating gear (c) Platen (d) Tractor feed unit (e) Pressure roller
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
Cut Sheet and Continuous Forms Switching Mechanism Refer to Figure 2-8 (below). Three different paper paths can be selected and set by the change lever. (a) TOP (for cut sheet) When the cut sheet is used in the manual mode or fed by the CSF (option), set the change lever at the position marked TOP. Operation The driving force of the platen gear (R) is transmitted to the idle gear by setting the change lever to the TOP position. However, this causes the idle gear to be disengaged from the change gear, leaving it free. At this time, the pressure rollers (at the rear and the front) are pressed securely to the platen to feed the cut sheet. At the same time, the switch lever positions between the rear switch and bottom switch, to confirm to the control board that you are in the cut sheet mode. In the cut sheet mode, the control board automatically feeds the sheet up to the print start position after pausing for the wait time stored in the menu. (b) REAR (Continuous forms from push tractor) When the change lever is set to REAR position, the change gear is engaged with the idle gear and the tractor gear to transmit the rotation of the platen to the push tractor shaft, and the continuous forms is fed from the push tractor. At the same time, the switch lever turns on the rear switch, to confirm to the control board that you are in the continuous forms mode. (c) BOTTOM (Continuous forms from bottom feeder) (option) When the change lever is set in the BOTTOM position, the rotation of the platen is transmitted to the drive gear of the bottom tractor feed unit through the idle gear to feed the paper which has been set in the bottom tractor feed. At the same time, the switch lever turns on the bottom switch, to confirm to the control board that you are in the continuous forms mode.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
(2) Cut-sheet feeder operation Refer to Figure 2-9 (below). The pulse motor used for the paper feed mechanism is mounted on the left of the frame, and the rotation of the motor is transmitted through decelerating gears (LF idle gear, platen gear) to the platen. When using cut-sheet paper, the change lever must be in the TOP position to grab the paper, while disengaging the push tractor. When the change lever is set to the TOP position, the cut sheet is automatically fed in up to the print start position after pausing for the wait time stored in the menu.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
(3) Continuous Forms Operation (Rear) See Figure 2-10 (below). The force transmitted to the platen, rotates the tractor gear through platen gear, the idler gear and the change gear. The rotation of the tractor gear makes the pin tractor belt rotate through a sheet feeder shaft, feeding the continuous forms.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
(4) Push and pull tractor mechanism (Option) Refer to Figure 2-11 (below). This mechanism consist of an optional pull tractor and a standard push tractor mechanism. This mechanism can perform forward and reverse feed by setting continuous forms to the push tractor and pull tractor. The rotation of the platen is transmitted to the push tractor and the pull tractor. Continuous forms are fed by these two tractors at the same time. To remove slack from the sheets, set the sheets according to the following procedure when using the push and pull tractors. 1 Set the change lever to the REAR position (setting the forms to the push tractor to feed). 2 Set the paper, which is fed in front of the platen, to the pull tractor. 3 Set the change lever to the TOP position and feed paper using the platen knob. 4 If paper slack is removed, set the change lever to the REAR position.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
(5) Pull tractor mechanism (option) Refer to Figure 2-12 (below). Bottom feed of continuous forms is possible only when an optional pull tractor unit is installed. The rotation of the platen is transmitted to the idle gear of the pull tractor unit through the platen gear at the left end of the platen. The rotation of the idle gear is transmitted to the drive gear, and continuous forms forms are fed by the pull tractor being rotated through the sheet feeder shaft.
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Service Guide ML390/ML391Turbo
Chapter 2 Theory of Operation
(6) Bottom Push Feed Operation (Option)
Refer to Figure 2-13 (below). The bottom push feed of the continuous forms is possible only when the bottom tractor feed unit is installed. When the platen rotates, the rotational force of the platen is transmitted through the tractor idle gear and the tractor change gear to the tractor drive gear of the bottom push tractor, and the sheet of paper is fed in to the print start position.
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Chapter 2 Theory of Operation
(7) Paper Clamp Mechanism Refer to Figure 2-14 (below). When setting the change lever to the BOTTOM , TOP or REAR position, the operation of the front release gear arm changes according to the position of the release cam. And at the same time, the position of the cam installed to the front release gear shaft changes, and the open and close of the pressure roller.
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Chapter 2 Theory of Operation
2.2.06 Paper Detection Mechanism Refer to Figure 2-15. The three paper detection types are listed below. 1. Cut Sheet Detection 2. Rear Feed Detection 3. Bottom Feed Detection. Cut Sheet Detection When the cut sheet is inserted, the point A is pushed backward and the paper near end lever B rotates counter clockwise (CCW). At this time, the rear sensor lever rotates counterclockwise (CCW), the rear sensor lever and pulls out of the rear and top paper end sensor to detect that the sheet is provided. The procedure for the paper end is made in the reverse order, that is, its detection is performed when the paper end sensor is blocked. Rear Feed Detection When the paper is fed from the push tractor, the point B is pushed to the front side and the paper near end lever A rotates clockwise (CW). At this time, the rear sensor lever rotates counterclockwise (CCW), and pulls out of the rear and top paper end sensor to detect that the paper is provided. The procedure for the paper end is made in the reverse order, that is, its detection is performed when the rear sensor lever intercepts the sensor. Bottom Feed Detection When the paper is fed from the bottom, the point C rotates clockwise (CW). When the bottom sensor lever rotates clockwise (CW), it pulls out of the bottom paper end sensor to detect that the paper is provided. The procedure for the paper end is made in the reverse order, that is, its detection is performed when the bottom sensor lever intercepts the sensor.
Top Line Print Mechanism Refer to Figure 2-16 (below) The top edge of the sheet is protected by the ribbon protector so that it can stop at a position near to the print head (0 tear off position) to start printing at the top end of the sheet, without causing the sheet to crumple or curl up. The printing starts at the front end of the sheet, and continues uni-directionally until the front end of the sheet gets to the inside of the pull up roller cover. After that, that printing continues bi-directionally.
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Chapter 2 Theory of Operation
2.2.07 Automatic Sheet Feed This function is used to feed in the sheet automatically up to the print start position when the cut sheet or the continuous forms is used. [Operational procedure] When Using Cut Sheet 1) Set the change lever to the TOP position. (See Figure 2-17 below.) 2) Insert a sheet of paper between the platen and the paper shoot. 3) After the lapse of time selected by the "wait time" in the menu, the LF motor starts its operation to feed the sheet of paper up to the print position. 4) When the default is selected, the sheet of paper is feed in up to the position 0.35 inches (first dot position) from the upper end of the sheet. However, the 0 tear off mechanism allows the printing at the front end of the sheet by changing the TOF position.
When Using Continuous Forms
1) Set the change lever either to the rear side or the bottom side position. (See Figure 2-17 above.) 2) Set a sheet of paper either to the push tractor or the bottom tractor. 3) Press the "FF/LOAD" switch. 4) The LF motor starts its operation to feed the paper up to the print start position. 5) The paper is fed in up to the TOF position (Factory default: 0.35 inches from the top).
When the ""FF/LOAD" switch is pushed down, the LF motor feeds in the sheet about 3 inches. When the LF motor completes the operation and the sheet has not been fed in, the feeding operating operation becomes, ineffective, thus resulting in the feeding jam. 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)
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Chapter 2 Theory of Operation
2.2.08 Paper Park Function (Continuous Forms) Continuous forms which have been inserted can be reversed automatically by using the "PARK" button on the operation panel. 1) Press the "PARK" button on the operation panel. 2) Reverse LF is started and paper is fed in reverse until paper end occurs or 19 inches maximum have been fed. 3) The paper is fed in reverse, to leave the paper on the push-tractor or bottom-tractor.
Alarm LED lights up when P.E. is not detected after 19 inches reverse feeding. Operator can press SEL key to turn off the ALARM LED then press PARK key to continue park function. This operation is required when the length of paper for parking is more than 19 inches.
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Service Guide ML390/ML391Turbo
Chapter 3 Assembly/Disassembly
ASSEMBLY/DISASSEMBLY This section explains the procedures for removing and installing various assemblies and units in the field. Description is mainly limited to the removal procedure; installation should basically be performed in the reverse sequence of the removal procedure.
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Chapter 3 Assembly/Disassembly
3.1 Precaution for Parts Replacement (1) Remove the AC cable and the interface cable before disassembling or assembling. (a) Turn off the AC power switch. Remove the AC input plug of the AC cable from the receptacle. Remove the AC cable from the inlet on the printer. (b) To connect the AC cable again, connect it to the inlet on the printer first, then insert the AC input plug into a receptacle. (2) Do not disassemble the printer as long as it is operating normally. (3) Do not remove unnecessary parts, and limit the disassembly area as much as pos-sible. (4) Use the designated service tools. (5) Carry out disassembly in the prescribed sequence; otherwise, damage to the parts may result. (6) It is advisable to temporarily install screws, snap rings and other small parts in their original positions to avoid losing them. (7) Whenever handling the microprocessors, ROM, RAM IC chips and boards, do not use gloves which may cause static electricity. (8) Do not place the printed circuit board directly on the equipment or on the floor. (9) If adjustment is specified in the middle of installation, follow the instructions.
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Chapter 3 Assembly/Disassembly
3.2 Service Tools Table 3.1 lists the tools necessary for replacing printed circuit boards and parts of units in the field.
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Service Guide ML390/ML391Turbo
Chapter 3 Assembly/Disassembly
3.3 Disassembly/Reassembly Procedure This section explains the assembly replacement procedures according to the following disassembly system. Parts Layout
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Service Guide ML390/ML391Turbo
Chapter 3 Assembly/Disassembly
How to Change Parts This section explains how to change parts and assemblies appearing in the disassembly diagram below.
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Chapter 3 Assembly/Disassembly
3.3.01 Printhead (1) Open the access over. (2) Pull up and rotate the head clamp 1 to unclamp the printhead 2 as shown fig. 3.3.1 (see below). (3) Disconnect the printhead 2 from PC connector 3. (4) To install, follow the removal steps in the reverse order. Notes on Installation: Important: Before inserting the printhead, note that there is a shim on the carriage frame (4), which hangs over the platen side of the frame. Be sure to replace the shim correctly. Improper positioning of this shim will severely affect the printhead gap and therefore affect print quality. (1) Insert the printhead 2 into the PC connector 3 while pushing it against the carriage frame 4. (2) The head clamp 1 must surely be sandwiched between printhead 2 and carriage frame 4 as shown fig. 3.3.2. (3) Be sure to check the gap between platen and printhead (see 4). (4) Be careful not to touch the print head while it is very hot.
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Chapter 3 Assembly/Disassembly
3.3.02 Ribbon Protector (1) Remove the printhead (see 3.3.1). (2) Open the pull-up roller cover 1. (3) Raise and remove the ribbon protector 2. (4) To install, follow the removal steps in the reverse order.
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Chapter 3 Assembly/Disassembly
3.3.03 Pull-up Roller Assy (1) Open the access cover 1. (2) Lift up the sheet guide Assy 4 to remove. Note: Please do after always remaining the sheet guide Assy 4 when the pull-up roller Assy 2 is installed and removed. (3) Tilting the pull-up roller Assy 2 toward the front, remove from the shaft of platen Assy 3. (4) To install, follow the removal steps in the reverse order.
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Chapter 3 Assembly/Disassembly
3.3.04 Upper Cover Assy, Access Cover Assy and Sheet Guide Assy (1) Pull off the platen knob 1. (2) Open the access cover Assy 4 toward the front to remove. (3) Lift up the sheet guide Assy 5 to remove. (4) Turn the change lever 2 toward the bottom position. (5) Insert a flat-blade screwdriver into grooves (5 places) (4 places for narrow type) of frame and twist to disengage claws of upper cover 3. (6) Raise the front side of upper cover Assy 3 and shift toward the rear to disengage claws (6 places) (5 places for narrow type) of frame. (7) Raise the upper cover Assy 3 to remove. (8) To install, follow the removal steps in the reverse order. Remark on assembly: Match the posts A at the both sides of the Sheet Guide 5 with the arrow marks on the upper cover. Push the Guide into the Cover.
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Chapter 3 Assembly/Disassembly
3.3.05 Gear Case Assy (1) Remove the printhead (see 3.3.1). (2) Remove the upper cover (see 3.3.4). (3) Move the carriage Assy to right hand side, remove two screws 1, and then remove the space motor 2. (4) Disconnect a carriage cable. (5) Disengage claws (4 places). Using a flat-blade screwdriver, push to widen the claw for easy disengagement.
(6) Remove the gear case Assy 3 in upper direction and release the carriage cable from the cable clamp of the gear case A (7) To install, follow the removal steps in the reverse order. Note on installation: (1) To assemble, align the direction of the SP motor axis 4 with the Gear Hole of the Gear Case assy. (2) Be sure to check, and adjust if necessary, the gap between platen and printhead (see 4-1).
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Chapter 3 Assembly/Disassembly
3.3.06 PC Connector (1) Remove the printhead (see 3.3.1). (2) Remove the upper cover (see 3.3.4). (3) Remove the gear case Assy (see 3.3.5). (4) Remove the PC connector 1 from the space motor Assy 2. (5) To install, follow the removal steps in the reverse order. Note on installation: (1) Do not touch the space motor 2 or terminals of PC connector 1. Also, take care to avoid dust or foreign matters. (2) After installation, check and adjust the gap between platen and printhead (see 4-1).
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Chapter 3 Assembly/Disassembly
3.3.07 Space Motor, Guide Roller Assy (1) Remove the printhead (see 3.3.1). (2) Remove the upper cover (see 3.3.4). (3) Remove the gear case Assy (see 3.3.5). (4) Remove the PC connector (see 3.3.6). (5) Remove screw 2, then the guide roller Assy 3 from the space motor 1. (6) Push down on the carriage cable and remove it. (7) Remove the screws (5), then remove the guide roller assembly (3) from the space motor assembly. (8) Remove the space motor (9) To install, follow the removal steps in the reverse order. Notes on installation: (1) Do not touch the terminals of space motor 1. Also, take care to avoid dust or foreign matters. (2) When installing the guide roller Assy 3, push portions A and B against the space motor 1. (3) When installing the space motor 1, align the face C with carriage frame 4 and push portion D against the frame. (4) After installation, check and adjust the gap between platen and printhead (see 4-1).
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Chapter 3 Assembly/Disassembly
3.3.08 Space Rack (1) Remove the printhead (see 3.3.1). (2) Remove the upper cover (see 3.3.4). (3) Remove the shim from the carriage frame. (4) Remove the gear case Assy (see 3.3.5). (5) Remove the space motor (see 3.3.7). (6) Remove the spring 1. (7) Disengage the claw on left side of space rack 2 from the frame, and remove the space rack 2 in upper direction. (8) To install, follow the removal steps in the reverse order. Note on installation: (1) After installation, check and adjust the gap between platen and printhead (see 4-1).
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Chapter 3 Assembly/Disassembly
3.3.09 Carriage Cable (1) Remove the printhead (see 3.3.1). (2) Remove the upper cover (see 3.3.4). (3) Remove the gear case Assy (see 3.3.5). (4) Remove the space motor (see 3.3.7). (5) Remove the space rack (3.3.8). (6) Remove two screws 1, release the driver board 2 and PCB sheet 9 by lifting clamp 8, and disconnect cable from connector 3, 4, 5, 6. (7) Remove carriage cable 7 from fasteners on frame. (8) To install, follow the removal steps in the reverse order. Note on installation: (1) Take care not to fold the carriage cable 7 during installation. Curve slightly the car-riage cable 7 when assembling into the fasteners. (2) Make sure that the paper end lever A will not contact the Paper end Sensor 0 when mounting the Driver Board.
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Chapter 3 Assembly/Disassembly
3.3.10 Backup Roller Holder Assy (1) Remove the printhead (see 3.3.1). (2) Remove the upper cover (see 3.3.4). (3) Remove the gear case Assy (see 3.3.5). (4) Remove the backup roller spring 2. Disengage claws (2 places) of roller holder from the carriage frame 1, and remove the backup roller holder assy 3. (5) To install, follow the removal steps in the reverse order.
Note: Small round hole with metal tip on back up roller holder assy 3 should be facing up when installing. 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)
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Chapter 3 Assembly/Disassembly
3.3.11 Platen Assy (1) Remove the printhead (see 3.3.1). (2) Remove the ribbon protector (see 3.3.2). (3) Remove the pull-up roller Assy (see 3.3.3). (4) Remove the upper cover (see 3.3.4). (5) Turn the change lever 1 to the bottom position. (6) Push in the lock levers 2 on both sides to unlock from the frame, then rotate them upward by 90°. (7) Remove the platen Assy 4 from base frame. (8) To install, follow the removal steps in the reverse order.
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Chapter 3 Assembly/Disassembly
3.3.12 Driver Board (SRXD) (1) Remove the upper cover (see 3.3.4). (2) Remove two screws 1, lift clamp 4, and release the driver board 2 and PCB sheet 5. (3) Disconnect all cables from driver board 2. (4) To install, follow the removal steps in the reverse order. Note on installation: (1) Insert one sensor lever 3 between sensor when installing the driver board 2.
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Chapter 3 Assembly/Disassembly
3.3.13 LF Motor (1) Remove the printhead (see 3.3.1). (2) Remove the ribbon protector (see 3.3.2). (3) Remove the pull-up roller Assy (see 3.3.3). (4) Remove the upper cover (see 3.3.4). (5) Remove the platen Assy (see 3.3.11). (6) Remove the driver board (see 3.3.12). (7) Remove the left FG plate 1. (8) Release the lock A to remove the LF motor 2. (9) To install, follow the removal steps in the reverse order. Remark on assembly: (1) Press the LF Motor Cable with a portion A of the Motor Plate.
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Chapter 3 Assembly/Disassembly
3.3.14 Operation Panel PCB (LEOP) (1) Remove the upper cover (see 3.3.4). (2) Disconnect the cable 1 from connector 3 of Driver board 2. (3) Disengage claws on both sides from the frame, and remove the operation panel 4. (4) Open claws (8 places) and remove the operation panel PCB 5 from the operation panel 4. (5) To install, follow the removal steps in the reverse order.
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Chapter 3 Assembly/Disassembly
3.3.15 Control/Power Supply Board (SRXC) (1) Remove the upper cover (see 3.3.4). (2) Disconnect two flexible cable 3 from the connector 2 the Control/Power Supply Board 1. (3) Remove the cable 5 from the connector 4 on the Control/Power Supply board 1. (4) Remove two screws 6, and remove the Control/Power Supply Board 1. (5) To install, follow the removal steps in the reverse order. Remark on assembly: (1) To mount the Control/Power Supply Board, set the change lever to the top position so that the Switch Lever 7 will not hooked on the microswitches 8.
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Chapter 3 Assembly/Disassembly
3.3.16 Transformer Assy (1) Remove the upper cover (see 3.3.4). (2) Remove AC inlet 1 and AC switch 2 from the frame guide. (3) Disconnect the cable 3 from the connector 4 on the Control/Power Supply Board 5. (4) Remove a screw 6 and disconnect ground cable 7. (5) Remove two screws 8 and shift the transformer Assy 9 to the left and remove it.
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Chapter 3 Assembly/Disassembly
3.3.17 Change Lever and Gears (1) Remove the upper cover (see 3.3.4). (2) Remove the reset spring 1, then remove the idle gear 2, the tractor gear 4 and the change gear 5. (3) Push back the protrusion of the Change Gear Shaft 6 with a flatblade screw driver to remove the change lever 3. (4) To perform mounting, follow the reverse procedure of removal. Remark on assembly: (1) To insert the change lever into the Change Gear Shaft 6, match the flat surface (D cut).
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Chapter 3 Assembly/Disassembly
3.3.18 Carriage Shaft (1) Remove the printhead (see 3.3.1). (2) Remove the upper cover (see 3.3.4). (3) Remove the driver board (see 3.3.12). Remove the FG plate (L) 2. (4) Slide the carriage shaft 1 to the left side (in the direction of the arrow) to remove. (5) To perform mounting, follow the reverse procedure of removal. Note on installation: (1) After installation, check and adjust the gap between platen and printhead (see 4-1).
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Chapter 3 Assembly/Disassembly
3.3.19 Paper Pan (1) Remove the printhead (see 3.3.1). (2) Remove the ribbon protector (see 3.3.2). (3) Remove the pull-up roller assy (see 3.3.3). (4) Remove the upper cover assy (see 3.3.4). (5) Remove the platen assy (see 3.3.11). (6) Release claws A . (7) Lift up the paper chute assy 1 and remove. (8) To perform mounting, follow the reverse procedure of removal.
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Chapter 3 Assembly/Disassembly
3.3.20 Rear Tractor Assy (1) Remove the printhead (see 3.3.1). (2) Remove the ribbon protector (see 3.3.2). (3) Remove the pull-up roller assy (see 3.3.3). (4) Remove the upper cover (see 3.3.4). (5) Remove the reset spring (see 3.3.17). (6) Remove the tractor gear 1. (7) Shift the drive shaft 2 to the right side to remove (in the direction of the arrow). (8) To perform mounting, follow the reverse procedure of removal. Remark on assembly: (1) When the Tractor Assy (L) 3 (R) 4 have been detached from the Drive Shaft, align the protrusions 5 of the Pin Tractor Wheels to the same direction before assembly.
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Chapter 3 Assembly/Disassembly
3.3.21 Rear Pressure Assy (1) Remove the upper cover (see 3.3.4). (2) Remove the change lever and gears (see 3.3.17). (3) Remove the paper pan (see 3.3.19). (4) Remove the rear pressure roller 1. (5) Rotate the release shaft 2 and move it to the left to detach the release shaft 2. Match the Main Frame Rib A with the protrusion B of the Release Shaft. (6) Remove rear pressure SP assy 3. (7) To install, follow the removal step in the reverse order. Note: (1) At mounting release shaft 2, pay attention to the gear engagement of release shaft 2, change arm lever 6, change gear shaft 7. (2) There are 5 Rear pressure Spring Assemblies. Use two pieces which have larger spring diameter on the right side. Use three remaining pieces on the left side (for ML391 Turbo). (3) Make sure that the Release Shaft 2 will be on top of the Support spring 4. (4) To assemble the Release Shaft 2, make sure that the protrusion of the switch lever 5 is in the U groove of the Release Shaft 2.
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Chapter 3 Assembly/Disassembly
3.3.22 Switch Lever (1) Remove the upper cover (see 3.3.4). (2) Remove the change lever and gears (see 3.3.17). (3) Remove the paper pan (see 3.3.19). (4) Remove the rear pressure assy (see 3.3.21). (5) Pull the Switch Lever toward you and remove it upward. (6) To install, follow the removal step in the reverse order. Remark on assembly: (1) At the time of the Switch Lever assembly, make sure that the Micro switch on the Main Board works properly.
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Service Guide ML390/ML391Turbo
Chapter 4 Adjustments
4. ADJUSTMENT (1) Be sure to carry out this adjustment with the printer mechanism mounted on the lower cover. (2) Be sure to carry out this adjustment operation on a level and highly rigid work table (flatness: less than 0.039 inch or 1 mm) so as to minimize adjustment error. 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)
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Chapter 4 Adjustments
4-1-1 Gap between the platen and the printhead No. 4-1-1 Item Gap between the platen and the printhead 1) Parallelism adjustment Specification Drawing Adjustment method It shall be measured at 3 points, the left end, the center and the right end of the platen. Adjustment method (1) Gap between the platen and the printhead at the left end and the right end shall be adjusted by rotating the adjust cam. (2) Set the adjust lever at the Range: 1. Press the adjust gear downward (in direction A) to push the adjust gear and the adjust gear out of mesh. 2) Initial adjustment .041 0.03 mm (3) Adjust the gap by rotating the adjust screw in direction B or C while the adjust lever and the adjust gear are disengaged. (4) After adjustment, mark the adjust cam position with a red pen.
Variation of value at the left, the center and the right shall be less then 0.02 mm
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Chapter 4 Adjustments
4-1-2 Measure variation of gap when range is changed.
No. 4-1-2
Item Measure variation of gap when range is changed.
Specification Gap = 0.71 0.05 at the range 5.
Drawing
Adjustment method
Gap between the contact and the monitor
.03mm or more
Confirm followings. Make sure that the gap between the contact and the motor PCB is 0.33 mm or more.
At the time of printing test, make sure that the contact touches the motor PCB and it becomes reduced speed mode when the adjust lever is set to range 2 and 4.
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Chapter 4 Adjustments
4-2 Gap between the platen and the paper pan
No. 4-2
Item Gap between the platen and the paper pan.
Specification 1 0.5
Drawing see below
Adjustment method Confirm followings. (1) When the change lever is set at Friction position, the gap between the platen and the paper pan at the rear side shall be 1 0.5mm. (2) When the change lever is set at Rear or Bottom position, the gap between the platen and the paper pan at the front side shall be 1 0.5 mm.
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Service Guide ML390/ML391Turbo
Chapter 4 Adjustments
4-3 Gap between the platen and the pressure roller
No. 4-3
Item Gap between the platen and the pressure roller
Specification
Drawing see below
Adjustment method Confirm followings. (1) When the change lever is set at Friction position, all the pressure rollers shall be pressed to the platen. (2) When the change lever is set at Rear or Bottom position, the gap between the platen and the pressure roller at the rear side shall be 3mm. The front pressure rollers shall be pressed to the platen.
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)
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Service Guide ML390/ML391Turbo
Chapter 4 Adjustments
4-4-1 Rotation of the push tractor
To confirm: The tractor gear shall rotate smoothly when the change lever is set at Friction 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)
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Service Guide ML390/ML391Turbo
Chapter 4 Adjustments
4-4-2 Backlash between gears
No. 4-4-2
Item Backlash between gears
Specification Approx. 0.05 to 0.11 mm
Drawing
Adjustment method To confirm: There shall be slight backlash between gears to allow smooth rotation of gears. (Backlash 0.05 to 0.11 mm)
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)
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Service Guide ML390/ML391Turbo
Chapter 4 Adjustments
4-5-1 Ribbon feed To confirm: Ribbon shall be fed smoothly when the carriage is moved from side to side.
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Service Guide ML390/ML391Turbo
Chapter 4 Adjustments
4-5-2 Running load to spacing mechanism To confirm: Make sure that the power is turned off at the time of measurement.
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Service Guide ML390/ML391Turbo
Chapter 4 Adjustments
4-6 Engagement of the double gear and the LF motor idle gear of the Platen Assy. To confirm: The idle gear of the LF motor and the platen gear (L) and the bias gear of the platen shall be in mesh in such way that the platen gear (L) and the bias gear rotate against each other to pinch the teeth of idle gear. The idle gear stays in mesh with the platen gear (L) and the bias gear and not locked. The bias gear and the platen gear shall be staggered by one teeth as shown in the drawing.
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Service Guide ML390/ML391Turbo
Chapter 5 Cleaning and Lubrication
5.1 Cleaning [Cautions] 1. Be sure to turn OFF the AC POWER switch before cleaning. Remove the AC Power cord from the printer. 2. Avoid dust inside the printer mechanism when cleaning. 3. If a lubricated part has been cleaned, be sure to apply lubricating oil to that portion after cleaning. (1) Cleaning Time When the equipment operating time has reached six months or 300 hours, whichever comes first. (2) Cleaning tools Dry cloth (soft cloth such as gauze), vacuum cleaner (3) Places to be cleaned Table 5.1 lists the places to be cleaned:
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Service Guide ML390/ML391Turbo
Chapter 5 Cleaning and Lubrication
5.2 Lubrication This printer is designed to be mainte