Ithaca 75, 76 User Manual

Disclaimer

Information in this publication is subject to change without notice and does not
represent a commitment on the part of Ithaca Peripherals Incorporated.
However, as product improvements become available, Ithaca Peripherals will
make every effort to provide updated information for the products described in
this publication.

Ithaca Peripherals cannot guarantee that changes in software and equipment
made by other manufacturers, and referred to in this publication, do not affect
the applicability of the information in this publication.

Copyright

Copyright © 1995
Ithaca Peripherals Incorporated
A Subsidiary of Tridex Corporation
Ithaca, New York U.S.A.

i

All Rights Reserved. No part of this publication may be reproduced, stored in a
retrieval system, or transmitted, in any form or by any means, mechanical,
photocopying, recording, or otherwise, without the prior written permission of
Ithaca Peripherals Incorporated.

First Edition, April 1995
Printed in U.S.A.

Trademarks

PcOS® is a registered trademark of Ithaca Peripherals Incorporated. Ithaca
Peripherals Incorporated is a subsidiary of Tridex Corporation.

ii

Federal Communications Commission
Radio Frequency Interference Statement

This equipment complies with the limits for a Class A computing device in
accordance with the specifications in Part 15 of FCC rules which are designed
to minimize radio frequency interference in the installation; however, there is no
guarantee that radio or television interference will not occur in any particular
installation. If this equipment does cause interference to radio or television
reception, which can be determined by turning the equipment off and on while
the radio or television is on, the user is encouraged to try to correct the
interference by one or more of the following measures:

♦ Reorient the radio or television receiving antenna;
♦ Relocate the printer with respect to the receiver;
♦ Move the printer away from the receiver;
♦ Plug the printer into a different outlet so that the printer and the receiver are

on different outlets.

If necessary, the user should consult the dealer or an experienced
radio/television technician for additional suggestions. The user may find the
following booklet prepared by the Federal Communications Commission
helpful: How to Identify and Resolve Radio/TV Interference Problems.

This booklet is available from the U.S. Government Printing Office,
Washington, DC 20402. Order stock number 004-000-00345-4.

Table of Contents iii

TABLE OF CONTENTS

PRODUCT INFORMATION 1

Communication Interfaces ..........................................................................2

Parallel Interface................................................................................2

Serial Interface................................................................................... 2

Technical Specifications.............................................................................4

Performance and Reliability ...............................................................4

Printing..............................................................................................4

Physical Dimensions .......................................................................... 4

Environmental Operating Limits.........................................................5

Power Requirements...........................................................................5

Consumable Products.........................................................................5

MAINTENANCE 7

Necessary Tools.........................................................................................7

Lubricating the Printer................................................................................ 8

Lubricating the Journal Take-up Gears and Pressure Roll Bearing ......8

Lubricating the Auto Cutter Assembly................................................9

Lubricating the Transport-Auto Cutter Assembly .............................10

Cleaning the Printer.................................................................................. 11

Making Adjustments.................................................................................11

Diagnosing the Print Quality ............................................................12

Adjusting the Platen Parallel to the Printhead ....................................13

Adjusting the Platen Air Gap ............................................................15

Replacing the Feed Roll Shaft ..........................................................17

Series 70 Maintenance Manualiv

DISASSEMBLY 19

Necessary Tools.......................................................................................19

Transport-Auto Cutter Assembly..............................................................20

Removing the Transport-Auto Cutter Assembly................................20

Disassembling the Transport-Auto Cutter Assembly.........................22

Auto Cutter Assembly (Without Transport) ..............................................26

Removing the Auto Cutter Assembly................................................26

Disassembling the Auto Cutter Assembly .........................................28

Base Assembly.........................................................................................30

AC Switch Assembly and Power Transformer...........................................32

Serial Interface Board ...............................................................................34

Control Board ..........................................................................................36

Interconnect Board ................................................................................... 38

Journal Bucket Assembly.......................................................................... 40

Removing the Journal Bucket Assembly ...........................................40

Disassembling the Journal Bucket Assembly .....................................42

Carriage Assembly...................................................................................44

Space Motor Assembly ....................................................................44

Carriage Shaft Bearing and Space Rack ...........................................46

Feed Roll Shaft.........................................................................................48

Linefeed Motor Assembly.........................................................................50

TROUBLESHOOTING 53

Determining the Problem .......................................................................... 53

Fixing the Problem ...................................................................................54

Checking Connections and Resistance....................................................... 72

Printhead .........................................................................................72

Space Motor Assembly ....................................................................73

Linefeed Motor ................................................................................ 74

Table of Contents v

APPENDIX A: SPARE PARTS 75

Standard Printer Parts ..............................................................................75

Optional Auto Cutter Parts.......................................................................77

APPENDIX B: THEORY OF OPERATION 79

Electrical Operation..................................................................................79

Circuit Operation.............................................................................79

Initialization.....................................................................................80

Communication Interface Control.....................................................80

Printhead Drive Circuit .................................................................... 81

Carriage Drive.................................................................................82

Linefeed...........................................................................................83

Alarm Circuits.................................................................................84

Power Supply ..................................................................................84

Mechanical Operation............................................................................... 85

Printhead Mechanism and Operation ................................................85

Space Mechanism and Operation ......................................................86

Ribbon Feed Mechanism and Operation............................................86

Paper Feed Mechanism and Operation..............................................87

Paper-Low Detection Mechanism and Operation...............................87

APPENDIX C: SCHEMATICS 89

Control Board ..........................................................................................90

Serial Interface Board...............................................................................94

Interconnect Board ................................................................................... 96

INDEX 97

Product Information 1

PRODUCT INFORMATION

Figure 1: Series 70 Printer

The Series 70 Printer models are 40-column, high-speed, impact printers and
are available in the following configurations.

Series 70
Models

Model 75
Model 76

Receipt
Printing

Journal
Printing

Paper
Low
Switch

Transport­Auto
Cutter
Option

Auto
Cutter

√√ √√ √√ √√ √√
√√ √√ √√ √√ √√

6.0 Inch
Receipt
Roll
Option

Series 70 Maintenance Manual2

COMMUNICATION INTERFACES

Parallel and serial communication interfaces are available.

PARALLEL INTERFACE

Figure 2: Connector for Parallel Interface

The parallel interface is standard on all models and is compatible with
Centronics.

SERIAL INTERFACE

Figure 3: Connector for Serial Interface

The RS-232C serial interface is optional on all models.

Figure 4: RS-232C Interface Board

RS-232C Specifications:

♦ 2k Buffer
♦ 19.2k Baud Maximum
♦ Read/Busy or XON/XOFF

Product Information 3

♦ Diagnostic Mode

Series 70 Maintenance Manual4

TECHNICAL SPECIFICATIONS

PERFORMANCE AND RELIABILITY

Performance
Print Speed Line Feed Time

196 Characters per Second 80 ms at Eight Lines per Inch

Reliability

PRINTING

Mean Time Between
Failure (MTBF)

25,000 Hours 15 Minutes 200 Million

Characters
Character Matrix Characters Per Line

7 x 7 Dot Utility Printing 40 at 17.1 Characters per Inch

Graphics
All Points Addressable (H x V) Bi-Directional Bit Image Graphics

60 x 72 Dots per Inch
120 x 144 Dots per Inch

Mean Time To
Repair (MTTR)

24 at 10 Characters per Inch
28 at 12 Characters per Inch

8 Bit Double Density

Print Head Life

Characters

PHYSICAL DIMENSIONS

Width Depth Height Weight

6.06 Inches 10.75 Inches 6.75 Inches 13 Pounds

ENVIRONMENTAL OPERATING LIMITS

Temperature Relative Humidity

Product Information 5

40-105° F
5-40° C

20-90%

POWER REQUIREMENTS

Voltage Frequency Operating Power

120, or 220/240 +/- 10% 50/60 Hz +/- 2% 37 Watts

CONSUMABLE PRODUCTS

Paper Number of Plies Dimensions

Receipt, Journal Paper (3.5 Inch
Diameter)

Receipt Paper (6.0 Inch
Diameter)

One or Two Ply Width: 3.25 Inches

Diameter: 3.50 Inches

One Ply Width: 3.25 inches

Diameter: 6.0 inches

Ithaca Peripherals
Part Number

100-1667 (3.5 Inch
Diameter)

98-0558 (3.5 Inch
Diameter)

100-2377 (6.0 Inch
Diameter)

Ribbon Cassette (12 per Box)
Ithaca Peripherals

Part Number

06-0560 Re-Inking Cassette Black
100-1823 Re-Inking Cassette Purple

Number
of Plies

One 50 240 Feet White

Two 50 125 Feet White, Canary

One 16 765 Feet White

Type Color

Rolls Per
Carton

Length Color

Series 70 Maintenance Manual6

MAINTENANCE

NECESSARY TOOLS

Caution: Using the wrong tools may cause personal injury or damage the

printer. Be sure to use the proper tools when maintaining or
servicing the Series 70 Printer.

The following table provides the necessary tools needed to properly maintain
the Series 70 Printer.

Maintenance 7

Nut Drivers Screwdrivers Ignition

Wrenches

7/32 Inch #0 Phillips 7/32 Inch Thickness Gauge: .012 Inch
1/4 Inch #1 Phillips 1/4 Inch
9/32 Inch #2 Phillips Hobby Knife
5/16 Inch Regular, Small Small Needle-Nose Pliers
3/8 Inch Regular, Large Paper Clip
7 mm

Miscellaneous

Allen Wrench: .050 Inch

8 Series 70 Maintenance Manual

LUBRICATING THE PRINTER

No periodic lubrication is required under normal printer use. Some lubrication
may be required with heavy printer use.

Caution: DO NOT use petroleum-based lubricants as they will damage the

plastic parts. Use a silicone-based lubrication.

Caution: Lubricating any points other than described here, such as the Space

Rack, will cause early and expensive failures to the printer.

LUBRICATING THE JOURNAL TAKE-UP GEARS AND
PRESSURE ROLL BEARING

Figure 5: Lubricating the Journal Take-up Gears and Pressure Roll Bearing

A = Journal Take-up Gears B = Pressure Roll Bearing

Lubricate the following points only:
♦ Journal Take-up Gears

When: as needed

♦ Pressure Roller Bearing

When: as needed

LUBRICATING THE AUTO CUTTER ASSEMBLY

Maintenance 9

Figure 6: Lubricating the Auto Cutter Assembly

A = Guide Wheel B = Pins for Shear Plate

Lubricate the following points only:
♦ Guide Wheel

When: every six months or 100,000 cycles

♦ Pins for Shear Plate

When: every six months or 100,000 cycles

10 Series 70 Maintenance Manual

LUBRICATING THE TRANSPORT-AUTO CUTTER ASSEMBLY

Figure 7: Lubricating the Transport-Auto Cutter Assembly

A = Guide Wheel B = Pins for Shear Plate

For ease in lubricating the Transport-Auto Cutter Assembly, remove it from the
printer. See “Transport-Auto Cutter Assembly” in the “Disassembly” chapter.
Lubricate the following points only:

♦ Guide Wheel

When: every six months or 100,000 cycles

♦ Pins for Shear Plate

When: every six months or 100,000 cycles

CLEANING THE PRINTER

Remove paper dust periodically by using a vacuum cleaner or air compressor.
Caution: Do not use alcohol or petroleum-based chemicals to clean the printer

as these will damage the plastic parts. The Carriage Rack is
particularly sensitive and will be permanently damaged if exposed to
these chemicals. Take special care not to get the cleaner on any
electronic components.

Maintenance 11

MAKING ADJUSTMENTS

The adjustments described in this section are required only to correct Printhead
drag or print quality flaws.

If the print density on a print sample is consistent from left to right and top to
bottom, and the Printhead does not drag, no adjustment is necessary. If the
Printhead drags, the gap may be too narrow. Increase the gap in order to get the
proper air gap of .012 inch on both left and right sides.

After a period of use, the Feed Roll Shaft may wear down to a point where
adjusting the gap will not correct the print problem. In this case, the Feed Roll
Shaft needs to be replaced. The Feed Roll Shaft also needs to be replaced when
it is cracked or “weather checked.” Refer to “Replacing the Feed Roll Shaft”
later in this chapter.

Note: Any time the Feed Roll Shaft is replaced, the bearings on either end

must also be replaced.
Check the Platen Air Gap and readjust it if necessary. See “Adjusting

the Platen Parallel to the Printhead” and “Adjusting the Platen Air
Gap” later in this chapter.

12 Series 70 Maintenance Manual

DIAGNOSING THE PRINT QUALITY

Use the flowchart on the following page to determine which procedure to use to
correct the specified print problems.

Figure 8: Flowchart for Print Quality Diagnosis

Note: If a print problem is not covered in this flowchart, refer to the

troubleshooting chart on page 53.

Maintenance 13

ADJUSTING THE PLATEN PARALLEL TO THE PRINTHEAD

Figure 9: Platen and Printhead

A = Ribbon Cassette D = Printhead
B = Range Adjustment Lever E = Adjusting Screw
C = Platen F = Adjusting Gear

14 Series 70 Maintenance Manual

1. Turn off the printer.

2. Remove all paper from the printer.

3. Remove the Ribbon Cassette (A).

4. Set the Range Adjustment Lever (B) to position 1 (towards the rear of the

printer).
The Range Adjustment Lever (B) is the blue lever on the Printhead (D).

5. Sight along the length of the Platen (C) from the side of the printer to
observe the parallelism of the air gap between the Platen (C) and the
Printhead (D).

6. Press down on the outer ring of the Adjusting Gear (F) with the
straightened end of a paper clip and turn the Adjusting Screw (E) with a #1
Phillips screwdriver until the gap at the top of the Printhead (D) is the same
as the gap at the bottom of the Printhead.

This adjustment changes the Printhead-to-Platen air gap. See the next
section, “Adjusting the Platen Air Gap.”

ADJUSTING THE PLATEN AIR GAP

Maintenance 15

Figure 10: Platen Air Gap

A = Ribbon Cassette E = Right Adjusting Screw
B = Carriage F = Printhead
C = Range Adjustment Lever G = Platen
D = Left Adjusting Screw

16 Series 70 Maintenance Manual

1. Turn off the printer.

2. Remove all paper from the printer.

3. Remove the Ribbon Cassette (A).

4. Set the Range Adjustment Lever (C) to position 1 (towards the rear of the
printer).

The Range Adjustment Lever is the blue lever on the Printhead (F).

5. Slide the Carriage (B) all the way to the left.

6. Adjust the Left Adjusting Screw (D) behind the Platen (G) with a 7/32 inch
nut driver until the gap between the Printhead (F) and the Platen is .012
inch.

7. Slide the Carriage (B) all the way to the right.

8. Adjust the Right Adjusting Screw (E) behind the Platen (G) with a 7/32
inch nut driver until the gap between the Printhead (F) and the Platen is
.012 inch.

9. Repeat steps five through eight until the gap is .012 all the way across the
length of the Platen traveled by the Printhead.

10. Replace the Ribbon Cassette and paper.

11. Turn on the printer.

REPLACING THE FEED ROLL SHAFT

Maintenance 17

Figure 11: Feed Roll Shaft

A = Printhead D = C-Clip
B = Print Head Clamp E = Feed Roll Bearings
C = Feed Roll Shaft

18 Series 70 Maintenance Manual

Note: Any time the Feed Roll Shaft is replaced, the Feed Roll Bearings on

either end must also be replaced.

1. Turn off the printer.

2. Remove the Ribbon Cassette.

3. Remove the Printhead (A) by lifting up on the Printhead Clamp (B) that is
located on the right side of the Printhead.

4. Grasp the Printhead (A) and pull straight up while pushing back on the
Forms Compensation Arm Assembly.

The Forms Compensation Arm Assembly is the assembly directly behind
the Printhead.

5. Remove the C-Clip (D) that is on the inside of the Feed Roll Bearing (E) on
the left-hand side of the Feed Roll Shaft (C).

Be careful not to lose the C-Clip. The tension is high and it will spring out
if you do not have a good hold on it.

6. Remove and discard the Feed Roll Shaft (C) and Feed Roll Bearings (E).
During the next four steps, you may need to push back on the Forms

Compensation Arm Assembly to get the Feed Roll Shaft out.
a. Slide the Feed Roll Shaft (C) to the left by pushing it through from the

right side with a screwdriver or other tool.

b. When the Feed Roll Shaft (C) comes out of the Right Side Frame, lift it

up enough to clear the frame.

c. Slide the Feed Roll Shaft (C) to the right until it clears the Left-Side

Frame.

d. Place the new Feed Roll Bearings (E) on the Feed Roll Shaft (C).

When replacing the Feed Roll Shaft, be sure to line up the Feed Roll
Bearings correctly. The two small notches should point toward the
cutaway in the frame.

7. Install the new Feed Roll Shaft and the C-Clip by reversing the above steps.

8. Replace the Printhead (A).

9. Check and readjust the Platen Air Gap.
See “Adjusting the Platen Air Gap” earlier in this chapter.

10. Replace the Ribbon Cassette.

11. Turn on the printer.

DISASSEMBLY

This chapter describes the disassembly procedures for the following items:

♦ Transport-Auto Cutter Assembly
♦ Base Assembly
♦ AC Switch Assembly and Power Transformer
♦ Serial Interface Board
♦ Control Board

Disassembly 19

♦ Interconnect Board
♦ Journal Bucket Assembly
♦ Carriage Assembly
♦ Feed Roll Shaft
♦ Linefeed Motor

NECESSARY TOOLS

Caution: Using the wrong tools may cause personal injury or damage the

printer. Be sure to use the proper tools when maintaining or
servicing the Series 70 Printer.

The following table provides the necessary tools needed to properly maintain
the Series 70 Printer.

Nut Drivers Screwdrivers Ignition

Miscellaneous

Wrenches

7/32 Inch #0 Phillips 7/32 Inch Thickness Gauge: .012 Inch
1/4 Inch #1 Phillips 1/4 Inch
9/32 Inch #2 Phillips Hobby Knife
5/16 Inch Regular, Small Small Needle-Nose Pliers
3/8 Inch Regular, Large Paper Clip
7 mm

Allen Wrench: .050 Inch

20 Series 70 Maintenance Manual

TRANSPORT-AUTO CUTTER ASSEMBLY

REMOVING THE TRANSPORT-AUTO CUTTER ASSEMBLY

Figure 12: Transport-Auto Cutter Assembly

A = Transport-Auto Cutter Assembly C = Forms Compensation Arm

B = Screws D = Ground Wire

Assembly

Disassembly 21

Note: This section describes removing the Transport-Auto Cutter Assembly

from the printer. See page 26 for removing the Auto Cutter Assembly
(without Transport).

1. Remove the Transport-Auto Cutter Assembly (A) from the Forms

Compensation Arm Assembly (C) by unscrewing the two screws (B) with a
#1 Phillips screwdriver.

The Ground Wire (D) is attached to the Forms Compensation Arm
Assembly (C) with one of the screws.

Do not try to unscrew the two 7/32 inch hex-head screws on the Platen.
They are for adjusting the Platen air gap.

2. Cut the tie wrap holding the cables to the frame.

3. Unplug the Transport Motor Cable and the Transport Sensor Cable from
the Interconnect Board.

Keep track of how the cables are routed.

Note: Reverse these procedures to reinstall the Transport-Auto Cutter

Assembly. Be sure to use new tie wraps to route the cables next to the
Base Assembly.

22 Series 70 Maintenance Manual

DISASSEMBLING THE TRANSPORT-AUTO CUTTER ASSEMBLY

Note: The folowing two sections describe disassembling the Transport-Auto

Cutter Assembly, beginning with the Right-Side Frame followed by the
Left-Side Frame (the side with the gears).

Right-Side Frame

Figure 13: Transport-Auto Cutter Assembly (1 of 2)

A = Transport Sensor
B = Lower Paper Chute H = E-Clip
C = Upper Paper Guide J = Right-Side Frame Screws
D = Right-Side Frame K = Nut (Sensor)
E = Cutter Drive Wheel Bearings L = Screw (Sensor)
F = Cutter Spring M = Paper Guide Pin

G = Hex-Head Screw & Lock Washer

Disassembly 23

Note: You may find it easier to remove the Transport Sensor and the Drive

Wheel Assembly (see the parts in the list below) before separating the
Right-Side Frame.

To remove the Transport Sensor (A) before separating the Right-Side
Frame (D), remove the Worm Wheel Gear (H, figure 14) to free the
Transport Sensor Cable. See the instructions under “Left-Side Frame.”

The Drive Wheel Assembly consists of the following items shown best
in figure 14:

Drive Wheel Roller (R, figure 14)
Drive Wheel Shaft (S, figure 14)
Drive Wheel Bearings (Q, figure 14)
Three E-Clips (B, figure 14)
Brass Pin (K, figure 14)
To remove the Drive Wheel Assembly before separating the Right-Side

Frame (D), see the instructions under “Left-Side Frame.”

Do the following steps to remove the Right-Side Frame (D) from the Transport­Auto Cutter Assembly. Refer to figure 13 on the facing page and figure 14 on
the next page.

1. Remove the E-Clip (H) from the shaft of the Auto Cutter (A, figure 14).

2. Remove the two screws (J) holding the Right-Side Frame (D) to the Lower
Paper Chute (B) with a #0 Phillips screwdriver.

3. Remove the hex-head screw and lock washer (G) holding the Right-Side
Frame (D) to the Back Plate (D, figure 14) with a 7/32 inch nut driver.

Be sure that the lock washer stays with the screw. Replacing the Back Plate
(D, figure 14) without the lock washer may cause it to become loose and
damage the printer.

4. Remove the Right-Side Frame (D) by pulling it straight out from the rest of
the Transport-Auto Cutter Assembly.

Be careful not to lose the Cutter Spring (F) from the Shear Plate (E, figure

14). When reinstalling the Right-Side Frame (D), be sure to line up the
Drive Wheel Bearing (E) on the Drive Wheel Assembly (R, S, Q, B, K,
figure 14) correctly. The two small notches should point toward the
cutaway in the Right-Side Frame (D).

5. Remove the Shear Plate (E, figure 14).

6. Remove the Transport Sensor (A) by unscrewing the screw (L) holding it to
the Upper Paper Guide (C) with a #1 Phillips screwdriver.

Keep track of the cable routing for reinstalling the Transport Sensor (A).
See the next illustration and instructions for freeing the Transport Sensor
Cable.

Note: Reverse these procedures to reassemble the Right-Side Frame.

24 Series 70 Maintenance Manual

Left-Side Frame

Figure 14: Transport-Auto Cutter Assembly (2 of 2)

A = Auto Cutter K = Brass Pin
B = E-Clip L = Cutter Motor Assembly
C = Hex-Head Screw & Lock Washer M = Cutter Motor Screws
D = Back Plate N = Micro Switch
E = Shear Plate O = Screws (Micro Switch)
F = Cutter Spring P = Spacers (Micro Switch)
G = Left-Side Frame Q = Drive Wheel Bearings
H = Worm Wheel Gear R = Drive Wheel Roller
J = Rotary Cam Gears S = Drive Wheel Shaft

Disassembly 25

1. Remove the small E-Clip (B) and the Worm Wheel Gear (H).

2. Cut the two tie wraps holding the Transport Sensor Cable to the Transport­Auto Cutter Assembly and the other cables.

You can now separate the Transport Sensor (A, figure 13) and cable from
the Transport-Auto Cutter Assembly. Keep track of the cable routing for
reinstalling the Transport Sensor.

3. Remove the outer E-Clip (B) and the Rotary Cam Gear (J) from the Drive
Wheel Assembly (R, S, Q, B, K) and slide the Drive Wheel Assembly out.

Don’t lose the Brass Pin (K) or the Drive Wheel Bearings (Q) from the
Drive Wheel Assembly. You do not need to remove the other E-Clips unless
you are disassembling the Drive Wheel Assembly.

When reinstalling the Drive Wheel Assembly, be sure to line up the Drive
Wheel Bearings (Q) correctly. The two small notches should point toward
the cutaway in the Left- and Right-Side Frames.

4. Remove the Upper Paper Guide (C, figure 13) by unsnapping it from the
Left-Side Frame (G).

Do not bend the Paper Guide Pin (M, figure 13) that connects the Upper
Paper Guide to the Lower Paper Chute (C, B, figure 13). When reinstalling
the Upper Paper Guide, hook it to the Left-Side Frame at both ends.

5. Remove the E-Clip (B) and the Rotary Cam Gear (J) from the Auto Cutter
(A) and slide the Auto Cutter out.

Don’t lose the Brass Pin (K) from the Auto Cutter (A).
When reinstalling the Auto Cutter (A), face the blade away from the Back

Plate (D) and place the Brass Pin (K) in the Auto Cutter so it is
perpendicular to the Auto Cutter blade. Place the Rotary Cam Gear (J) on
the Auto Cutter with the flat side of the inside portion of the gear facing the
Micro Switch (N). If the Auto Cutter is not installed correctly, it will not
work. Do not put the Rotary Cam Gear (J) in upside-down.

6. Remove the remaining two E-Clips (B) and Rotary Cam Gears (J).

7. Remove the two screws (M) holding the Cutter Motor Assembly (L) to the
Left-Side Frame with a #0 Phillips screwdriver.

8. Remove the Micro Switch (N) from the Left-Side Frame (G) by unscrewing
the two screws (O) with a .050 inch Allen wrench.

Be careful not to lose the Spacers (P) behind the Micro Switch (N).

9. Remove the Back Plate (D) from the Left-Side Frame (G) by unscrewing
the hex head screw and lock washer (C) with a 7/32 inch nut driver.

Be sure that the lock washer stays with the hex head screw. Replacing the
Back Plate (D) without the lock washer may cause the Back Plate to
become loose and damage the printer.

26 Series 70 Maintenance Manual

10. Remove the Lower Paper Chute (B, figure 13) from the Left-Side Frame
(G) by unscrewing the two screws (J, figure 13) with a #0 Phillips
screwdriver.

Note: Reverse these procedures to reassemble the Left-Side Frame.

AUTO CUTTER ASSEMBLY (WITHOUT TRANSPORT)

REMOVING THE AUTO CUTTER ASSEMBLY

Figure 15: Auto Cutter Assembly (without Transport)

Disassembly 27

A = Auto Cutter Assembly C = Forms Compensation Arm

Assembly

B = Screws D = Ground Wire

Note: This section describes removing the Auto Cutter Assembly from the

printer. See page 20 for removing the Transport-Auto Cutter
Assembly).

1. Remove the two screws (B) holding the Auto Cutter Assembly (A) to the

Forms Compensation Arm Assembly (C) with a #1 Phillips screw driver.
The Ground Wire (D) is attached to the Forms Compensation Arm

Assembly with one of the screws.
Do not try to unscrew the two 7/32 inch hex-head screws on the platen.

They are for adjusting the Platen air gap.

2. Cut the tie wrap holding the Cutter Motor cables to the frame.

3. Unplug the Cutter Motor Cables from the Interconnect Board.
Keep track of how the cables are routed.

Note: Reverse these procedures to reinstall the Auto Cutter Assembly. Be

sure to use a new tie wrap to route the cables next to the frame.

28 Series 70 Maintenance Manual

DISASSEMBLING THE AUTO CUTTER ASSEMBLY

Figure 16: Auto Cutter Assembly

A = Auto Cutter Gear Shield M = Left-Side Frame
B = Screw N = Worm Wheel Gear
C = Rotary Shield O = C-Clip
D = Auto Cutter P = Rotary Cam Gear
E = C-Clip Q = Brass Pin
F = Hex-Head Screw & Lock Washer R = Cutter Motor Assembly
G = Right-Side Frame S = Screws (Cutter Motor)
H = Back Plate T = Micro Switch
J = Shear Plate U = Screws (Micro Switch)
K = Cutter Spring V = Spacers (Micro Switch)
L = C-Clip

Disassembly 29

1. Remove the Auto Cutter Gear Shield (A) by removing the Screw (B)
holding the Auto Cutter Gear Shield to the Left-Side Frame (M) with a #1
Phillips screwdriver.

2. Remove the Rotary Shield (C) by lifting it out and down from the top.

3. Remove the E-Clip (E) on the right-hand side of the Auto Cutter (D).

4. Remove the Hex-Head Screw and Lock Washer (F) holding the Right-Side
Frame (G) to the Back Plate (H) with a 7/32 inch nut driver.

5. Carefully remove the Right-Side Frame (G) while at the same time
removing the Shear Plate (J) and Cutter Spring (K).

6. Remove the Worm Wheel Gear (N) by removing the E-Clip (L) holding the
Worm Wheel Gear to the Left-Side Frame (M).

7. Remove the E-Clip (O) and the Rotary Cam Gear (P) from the Auto Cutter
(D) and slide the Auto Cutter out.

Be careful when removing the Rotary Cam Gear (P) that you do not
damage the Micro Switch (T) underneath the gear.

Be careful not to lose the Brass Pin (Q) from the Auto Cutter.
When reinstalling the Auto Cutter (D), face the blade away from the Back

Plate (H) and place the Brass Pin (Q) in the Auto Cutter so it is
perpendicular to the Auto Cutter blade. Place the Rotary Cam Gear (P) on
the Auto Cutter with the flat side of the inside portion of the gear facing the
Micro Switch (T). If the Auto Cutter is not installed correctly, it will not
work. Do not put the Rotary Cam Gear in upside-down.

8. Remove the two Screws (S) holding the Cutter Motor Assembly to the Left­Side Frame (M) with a #0 Phillips screwdriver.

9. Remove the two Screws (U) holding the Micro Switch (T) to the Left-Side
Frame (M) with a .050 inch Allen wrench.

Be careful not to lose the Spacers (V) behind the Micro Switch (T).

11. Remove the Hex Head Screw and Lock Washer (F) holding the Left-Side
Frame (M) to the Back Plate (H) with a 7/32 inch nut driver.

Note: Reverse these procedures to reassemble the Auto Cutter Assembly.

30 Series 70 Maintenance Manual

BASE ASSEMBLY

Figure 17: Base Assembly

Disassembly 31

A = Base Assembly C = AC Power Transformer Cable
B = Sems Screws

Note: Remove the Base Assembly from the rest of the printer before

disassembling the printer. After removing the Base Assembly, you can
then remove the AC Switch Assembly and the AC Power Transformer
from the Base Assembly.

1. Turn off the printer and unplug the Power Cord.

2. Disconnect the Communication Cable.

3. Remove all paper from the printer.

4. Remove the four Sems Screws and lock washers (B) from the top side of
the Base Assembly (A) with a #2 Phillips screwdriver as shown in the
illustration.

5. Lift the printer up from the right side an inch or two and disconnect the AC
Power Transformer Cable (C) from the Control Board.

6. Separate the printer from the Base Assembly.

7. Turn the printer upside-down to avoid damaging the boards.

Note: Reverse these procedures to reattach the Base Assembly to the printer.

32 Series 70 Maintenance Manual

AC SWITCH ASSEMBLY AND POWER TRANSFORMER

Figure 18: AC Switch Assembly and Power Transformer (1 of 2)

Note: This assembly may vary slightly depending on the model.

A = AC Power Transformer E = AC Switch Cover Plate
B = AC Plug F = AC Switch Cover Plate Screws
C = Nut and Washer G = AC Plug Screws
D = Ground Wire, Nut, and Washer

Disassembly 33

Note: Before removing the AC Switch Assembly and Power Transformer,

you must separate the Base Assembly from the printer. Refer to “Base
Assembly” earlier in this chapter.

1. Remove the nut and washer (C) holding the AC Power Transformer (A) to
the Base Assembly with a 3/8 inch nut driver.

2. Remove the AC Switch Cover Plate (E) from the Base Assembly by
unscrewing the three screws (F) with a #2 Phillips screwdriver.

3. Remove the AC Plug (B) from the Base Assembly by unscrewing the two
screws (G) with a #1 Phillips screwdriver.

Use needle-nose pliers or a 7/32 inch end wrench to capture the nuts.

4. Remove the nut and washer holding the ground wire (D) to the Base
Assembly with a 9/32 inch nut driver.

5. Pull up on the AC Power Transformer (A) until it clears the screw, then
slide it out of the base.

The screw is riveted to the bottom of the Base and cannot be removed.

Figure 19: AC Switch Assembly and Power Transformer (2 of 2)

A = AC Power Transformer C = AC Plug
B = AC Switch Assembly

6. Unsolder the two leads from the AC Power Transformer (A) to separate the
AC Switch Assembly (B) from the AC Power Transformer.

Do not further disassemble the AC Switch Assembly. The AC Plug (C) is
hard-wired to the AC Switch Assembly and should not be removed.

Note: Reverse these procedures to reinstall the AC Switch Assembly and AC

Power Transformer.

34 Series 70 Maintenance Manual

SERIAL INTERFACE BOARD

Figure 20: Serial Interface Board

A = Serial Interface Board C = Glue
B = Screws D = Standoffs

Disassembly 35

Note: Before removing the Serial Interface Board, you must separate the

printer from the Base Assembly. Refer to “Base Assembly” earlier in
this chapter. For ease in removing any of the boards, remove the
Transport-Auto Cutter Assembly from the printer. Refer to “Transport­Auto Cutter Assembly” earlier in this chapter.

1. Turn the printer upside down.

2. Remove the two screws (B) on either side of the metal D-shell connector
which holds the Serial Interface Board (A) to the Control Board with a 7/32
inch nut driver.

3. Remove the glue (C) holding the Serial Interface Board (A) to the Control
Board with a small knife or a pair of small needle-nose pliers.

4. Remove the Serial Interface Board (A).
Be careful not to bend the pins on the Control Board.

Note: Reverse these procedures to reinstall the Serial Interface Board.

36 Series 70 Maintenance Manual

CONTROL BOARD

Figure 21: Control Board

A = Control Board B = Screws

Disassembly 37

Note: Before removing the Control Board, you must separate the printer from

the Base Assembly and remove the Serial Interface Board, if present.
Refer to “Base Assembly” and “Serial Interface Board” earlier in this
chapter. For ease in removing any of the boards, remove the Transport­Auto Cutter Assembly from the printer. Refer to “Transport-Auto
Cutter Assembly” earlier in this chapter.

1. Remove the five screws (B) holding the Control Board (A) to the printer
with a 7/32 inch nut driver.

Note the position of the two longer screws in the illustration.

Caution: Do not bend the posts protruding from the bottom of the board

during the next step.

2. Gently pull the Control Board (A) straight out at the corner near the fuse.

Note: Reverse these procedures to reinstall the Control Board.

When reinstalling the Control Board, carefully insert the square posts
protruding from the bottom of the Control Board into the proper holes
on the Interconnect Board. If this is not done properly, the
Transformer, Control Board, and Interconnect Board may be damaged.

38 Series 70 Maintenance Manual

INTERCONNECT BOARD

Figure 22: Interconnect Board

Disassembly 39

A = Interconnect Board F = Cable Clamp
B = Paper Low Switch Cable G = Contact Rubber
C = Journal Take-up Motor Cable H = Carriage Ribbon Cable
D = Test Switch Cable J = Pressure Bar
E = Brass Standoffs

Note: Before removing the Interconnect Board, you must separate the printer

from the Base Assembly, remove the Serial Interface Board (if used),
and the Control Board. Refer to “Base Assembly,” “Serial Interface
Board,” and “Control Board” earlier in this chapter. For ease in
removing any of the boards, remove the Transport-Auto Cutter
Assembly from the printer.

1. Turn the printer right-side up.

2. Disconnect the following cables from the Interconnect Board:

♦ Paper Low Switch (routing of the cable differs depending on the model)
♦ Test Switch
♦ Journal Take-up Motor

3. Turn the printer upside-down.

4. Remove the Carriage Cable Assembly (F, G, H, J) from the Interconnect
Board by sliding it off the board.

When reinstalling, be sure that the cable contacts the board directly.
You do not need to separate the Pressure Bar (J) from the Cable Clamp (F).

If any of the pieces are broken, you can separate them in order to replace
the broken parts.

To separate the parts, carefully bend the metal tabs of the Cable Clamp (F)
outward slightly with a pair of long needle-nose pliers. Don’t bend the
plastic tabs on the Pressure Bar (J) as they are easily broken. Be careful not
to damage the Carriage Ribbon Cable (H).

5. Remove the three Brass Standoffs (E) holding the Interconnect Board (A)
to the printer with a 1/4 inch nut driver.

Note: Reverse these procedures to reinstall the Interconnect Board.

40 Series 70 Maintenance Manual

JOURNAL BUCKET ASSEMBLY

REMOVING THE JOURNAL BUCKET ASSEMBLY

Figure 23: Journal Bucket Assembly (1 of 2)

Disassembly 41

A = Journal Bucket Assembly C = Washers
B = Nuts D = Helper Springs

Note: You do not need to separate the Printer from the Base Assembly, or

remove any of the boards to remove the Journal Bucket Assembly. If
you have already removed the Base Assembly and the boards, turn the
printer right-side up, but be careful not to damage the Carriage Cable.

1. If you have not already done so, unplug the following cables:

♦ Paper Low Switch (routing of the cable differs depending on the model)
♦ Journal Take-up Motor

2. Remove the three nuts (B) and washers (C) holding the Journal Bucket
Assembly (A) to the printer frame with a 9/32 inch nut driver.

The screws are riveted to the frame and cannot be taken out.

3. Pull the Journal Bucket Assembly (A) up until it clears the screws, then out
to remove it.

Be careful not to lose the Helper Springs (D) on the Forms Compensation
Arm.

Note: Reverse these procedures to reinstall the Journal Bucket Assembly.

42 Series 70 Maintenance Manual

DISASSEMBLING THE JOURNAL BUCKET ASSEMBLY

Figure 24: Journal Bucket Assembly (2 of 2)

Note: This assembly may vary slightly depending on the model.

A = Journal Bucket Assembly F = Switch Gears
B = Left Paper Supply Plate G = E-Clips
C = Right Paper Supply Plate H = Journal Take-up Motor
D = Nuts J = Journal Take-up Motor Screws
E = Paper Low Switch

Disassembly 43

Note: The following instructions describe disassembling the Journal Bucket

Assembly with the Journal Take-up Motor and gears. Some models do
not have the journal take-up option. On those models, you only need to
remove the Paper Low Switch and the Paper Supply Plates (plastic
pieces on the sides of the bucket) to disassemble the Journal Bucket
Assembly.

1. Remove the E-Clips (G) and Switch Gears (F) from the Journal Bucket
Assembly (A).

2. Remove the two screws (J) holding the Journal Take-up Motor (H) to the
Journal Bucket Assembly (A) with a #0 Phillips screwdriver.

3. Remove the nuts (D) holding the Paper Supply Plates (B, C) to the sides of
the Journal Bucket Assembly (A) with a 9/32 inch nut driver.

4. Gently pry out the Paper Low Switch (E) from the Journal Bucket
Assembly (A).

Squeeze the tabs on the Paper Low Switch (E) or insert a screwdriver under
the switch to remove it.

Note: Reverse these procedures to reassemble the Journal Bucket Assembly.

44 Series 70 Maintenance Manual

CARRIAGE ASSEMBLY

SPACE MOTOR ASSEMBLY

Figure 25: Space Motor Assembly

Disassembly 45

A = Printhead E = Space Motor
B = Ribbon Cassette F = Screw
C = Ribbon Feed Gear Assembly G = Screws
D = Carriage Cable H = Slider Assembly

Note: You do not need to separate the Printer from the Base Assembly or

remove any of the boards to remove the Carriage Assembly. If you
have already removed the Base Assembly and the boards, turn the
printer right-side up, but be careful not to damage the Carriage Cable.

1. Remove the Ribbon Cassette (B).

2. Lift up on the printhead clamp located on the right side of the Printhead (A)
and remove the Printhead.

3. Rotate the Slider Assembly (H) away from the Space Motor Assembly and
printer frame by loosening the screw (F) with a #1 Phillips screwdriver.

You do not need to remove this screw.

4. Remove the Space Motor Assembly by unscrewing the two screws (G)
holding the Space Motor Assembly to the Carriage Assembly with a #1
Phillips screwdriver.

Caution: Do not separate the top and bottom halves of the Ribbon Feed Gear

Assembly in the next step or gears will fall out of the assembly.

5. Remove the Ribbon Feed Gear Assembly (C) from the Space Motor (E) by
pulling the four tabs outward.

a. Pull the two tabs outward that are closest to the Carriage Cable (D).
b. Next, pull the other two tabs outward.

Caution: Be careful when handling the ribbon cable. It will crease easily.

Avoid touching any of the contact areas.

6. Carefully disconnect the Carriage Cable (D) by separating it from the
Ribbon Feed Gear Assembly (C).

Note: Reverse these procedures to reinstall the Space Motor Assembly.
Note: After the Space Motor Assembly has been reinstalled, check the

spacing between the Space Motor Assembly and the Space Rack (see
F, Figure 26). Adjust the space to .012 inches with a Thickness Gauge.
Loosen the two screws (G) as needed to make the adjustment.

Check the platen parallelism and air gap and readjust if necessary. See
“Adjusting the Platen Parallel to the Printhead” and “Adjusting the
Platen Air Gap” in the “Maintenance” chapter.

46 Series 70 Maintenance Manual

CARRIAGE SHAFT BEARING AND SPACE RACK

Figure 26: Carriage Shaft Bearing and Space Rack

A = Carriage Shaft D = Carriage Shaft Stop Blocks
B = Screws E = Carriage Assembly
C = Base Plate F = Space Rack

Disassembly 47

Note: Before removing the Carriage Shaft Bearing and Space Rack, you must

remove the Space Motor Assembly. Refer to the previous section,
“Space Motor Assembly.”

1. Remove the screws (B) at each end of the Carriage Shaft (A) with a #1
Phillips screwdriver.

2. Gently pull the Carriage Assembly (E) and Carriage Shaft (A) from the
Base Plate (C).

3. Remove the rubber U-shaped Carriage Shaft Stop Blocks (D) located at
both ends of the Carriage Shaft (A).

4. Slide the Carriage Assembly (E) off the Carriage Shaft (A).

5. Remove the Space Rack (F) by gently pulling up on the left hand side.

Note: Reverse these procedures to reinstall the Carriage Shaft Bearing and

Space Rack.
Remember to install the U-shaped Carriage Shaft Stop Blocks (D).

Note: After the Carriage Shaft Bearing and Space Rack have been reinstalled,

check the Platen Air Gap and readjust it if necessary. See “Adjusting
the Platen Parallel to the Printhead” and “Adjusting the Platen Air
Gap” in the “Maintenance” chapter.

48 Series 70 Maintenance Manual

FEED ROLL SHAFT

Figure 27: Feed Roll Shaft

A = Printhead D = C-Clip
B = Printhead Clamp E = Feed Roll Bearings
C = Feed Roll Shaft

Disassembly 49

Note: You do not need to remove any items from the printer to remove the

Feed Roll Shaft, except for the Ribbon Cassette and the Printhead. Any
time the Feed Roll Shaft is replaced, the Feed Roll Bearings on either
end must also be replaced.

1. Remove the Ribbon Cassette.

2. Remove the Printhead (A) by lifting up on the Printhead Clamp (B) that is
located on the right side of the Printhead.

3. Grasp the Printhead (A) and pull straight up while pushing back on the
Forms Compensation Arm Assembly.

The Forms Compensation Arm Assembly is the assembly directly behind
the Printhead.

4. Remove the C-Clip (D) that is on the inside of the Feed Roll Bearing (E) on
the left-hand side of the Feed Roll Shaft (C).

Be careful not to lose the C-Clip. The tension is high and it will spring out
if you do not have a good hold on it.

Note: During the next four steps, you may need to push back on the Forms

Compensation Arm Assembly to get the Feed Roll Shaft out. If the
Journal Bucket Assembly has been removed, you may find it easier to
pivot the Forms Compensation Arm Assembly so that it is lying flat
and out of your way.

5. Slide the Feed Roll Shaft (C) to the left by pushing it through from the right
side with a screwdriver or other tool.

6. When the Feed Roll Shaft (C) comes out of the Right Side Frame, lift it up
enough to clear the frame.

7. Slide the Feed Roll Shaft (C) to the right until it clears the Left-Side Frame.

8. Place the new Feed Roll Bearings (E) on the Feed Roll Shaft (C).
When replacing the Feed Roll Shaft, be sure to line up the Feed Roll

Bearings correctly. The two small notches should point toward the cutaway
in the frame.

Note: Reverse these procedures to reinstall the Feed Roll Shaft.
Note: Check and readjust the Platen Air Gap. See “Adjusting the Platen Air

Gap” in the “Maintenance” chapter.

50 Series 70 Maintenance Manual

LINEFEED MOTOR ASSEMBLY

Figure 28: Linefeed Motor Assembly

A = Base Plate C = Nut
B = Linefeed Motor Assembly D = Clip

Disassembly 51

Note: Before removing the Linefeed Motor, you must separate the printer

from the Base Assembly, remove the boards, and remove the Journal
Bucket Assembly. See “Base Assembly,” the sections for the boards,
and “Journal Bucket Assembly” earlier in this chapter.

1. Remove the nut (C) holding the Linefeed Motor Assembly (B) to the Base
Plate (A).

2. Remove the clip (D) at the bottom of the Base Plate (A) holding the
Linefeed Motor Assembly (B) to the Base Plate.

3. Remove the Linefeed Motor Assembly (B).
There are two gears remaining. The bottom gear can be removed by

removing the E-Clip. The top gear cannot be removed.

Note: Reverse these procedures to reinstall the Linefeed Motor Assembly.

52 Series 70 Maintenance Manual

TROUBLESHOOTING

This chapter provides solutions to problems that may occur with the printer.
Use the table to determine the problem, then refer to the specified flowchart that
describes the corrective action for that problem. The flowcharts are on the
following pages and are identified by the number referred to in the table.

Following the flowcharts is a section that describes checking the connection
circuits and resistance for the Printhead, Space Motor, and Linefeed Motor.

Troubleshooting 53

DETERMINING THE PROBLEM

When Problem
Occurs

Trouble at Power On Printer is dead; no voltages on control board 1

Trouble During Data
Reception or Printing

Description of Problem Refer to

The Carriage does not move 2
Carriage does not operate normally: runaway,

vibration, incomplete homing
Carriage homes normally, but LED comes on

(constant or flash)
Fuse on the Power Supply blows at power-up 5
Fuse on the Control Board blows (SLMR

blows)
Spacing or printing does not occur 7

Spacing operates normally, but printer does
not print

Printer stops printing 9
Wrong characters are printed or some

characters are not printed

Flowchart

3

4

6

8

10

Some dots do not print 11
Print is not dark enough 12
Printer does not line feed during printing 13
Fuse on Power Supply Board blows during

printing

14

54 Series 70 Maintenance Manual

FIXING THE PROBLEM

The troubleshooting flowcharts are identified by a circled number that
corresponds with the problems listed in the table on the previous page. They are
presented in the order listed in the table.

Flowchart
Reference

Flowchart
Reference

Flowchart
Reference

1 5 11
2 6 12
2-1 7 13
2-2 8 14
3 9
4 10

Note: References to letters in the flowcharts refer to items called out in Figure

45 on page 71. Refer to the respective sections in the “Disassembly”
chapter for information on replacing modules or assessemblies as
instructed in the flowcharts. For example, if the flowchart tells you to
replace the AC Switch Assembly, refer to the “AC Switch Assembly”
section in the “Disassembly” chapter.

Troubleshooting 55

Figure 29: Flowchart 1

56 Series 70 Maintenance Manual

Figure 30: Flowchart 2

Figure 31: Flowchart 2-1

Troubleshooting 57

58 Series 70 Maintenance Manual

Figure 32: Flowchart 2-2

Troubleshooting 59

Figure 33: Flowchart 3

60 Series 70 Maintenance Manual

Figure 34: Flowchart 4

Troubleshooting 61

Figure 35: Flowchart 5

62 Series 70 Maintenance Manual

Figure 36: Flowchart 6

Troubleshooting 63

Figure 37: Flowchart 7

64 Series 70 Maintenance Manual

Figure 38: Flowchart 8

Troubleshooting 65

Figure 39: Flowchart 9

66 Series 70 Maintenance Manual

Figure 40: Flowchart 10

Troubleshooting 67

Figure 41: Flowchart 11

68 Series 70 Maintenance Manual

Figure 42: Flowchart 12

Troubleshooting 69

Figure 43: Flowchart 13

70 Series 70 Maintenance Manual

Figure 44: Flowchart 14

Troubleshooting 71

Figure 45: Connections

Note: This illustration is referenced by the letters in the troubleshooting

flowcharts and in the illustrations on the following three pages.

72 Series 70 Maintenance Manual

CHECKING CONNECTIONS AND RESISTANCE

PRINTHEAD

The following illustration shows the connection circuit for the Printhead and the
rear of the Printhead. The resistance should be approximately 20 ohms.

Pins at Connection Signals Pins on

Printhead

Common
Wire #1
Wire #2
Wire #3
Wire #4
Wire #5
Wire #6
Wire #7
Wire #8
Wire #9

Figure 46: Printhead Pin Assignments

5, 6, 7
14
13
1
12
2
11
1
10
4

Rear of Printhead

Note: The circled letters refer to the respective locations marked in figure 45

The following example shows how to measure the resistance.
Use 5, 6, 7 on printhead and measure with a meter to pin 14 at location A. The

resistance should read 20 ohms. This procedure checks the circuit of wire
number one of the printhead. Refer to Figure 45 on page 71.

on page 71.

SPACE MOTOR ASSEMBLY

The following illustration shows the connection circuit for the Space Motor
Assembly and the pins on the Space Motor. The resistance should be
approximately 21 ohms between pads 17 and 16, 16 and 18, and 17 and 18 on
the Space Motor.

Pins at Connection Signals Pins on Space Motor

Troubleshooting 73

V
U

W

A

B

Figure 47: Space Motor Pin Assignments

15
14

16

Note: The circled letters refer to the respective locations marked in figure 45

on page 71.

74 Series 70 Maintenance Manual

LINEFEED MOTOR

The following illustration shows the connection circuit for the Linefeed Motor.
The resistance of each coil should be approximately 70 ohms between pads 38
and 39, 39 and 40, 37 and 36, and 36 and 35 on the Linefeed Motor.

Pins at Connection Signals Pins on Linefeed Motor

Phase One

Common

Phase Three
Phase Two

Common
Phase Four

Figure 48: Linefeed Motor Pin Assignments

3

2

1
4

5
6

Note: The circled letters refer to the respective locations marked in figure 45

on page 71.

Appendix A: Spare Parts 75

APPENDIX A: SPARE PARTS

STANDARD PRINTER PARTS

Description Part Number
AC Switch Assembly

A/C Switch Assembly (110 VAC) 98-2132
A/C Switch Assembly (220 VAC) 98-1828

Board Assembly

Board Assembly, IPI Auto-Cut 09-2155
Board Assembly, Main Control, Parallel 98-2165
Board Assembly, Main Control, Serial 98-2164
Board, Serial Interface (without socket) 283-0600001
Board, Serial Interface (with socket) 09-2208

Carriage

Carriage Cable 98-2512
Carriage Cable Contact Rubber, IPI Board 06-0568
Carriage Cable Cord Clamp, IPI Board 06-0569
Carriage Cable Mylar, Printhead End 06-0577
Carriage Cable Pressure Rubber, PH End 06-0576
Carriage Cable Tape 06-0710
Carriage Roller 06-0570
Carriage Shaft 06-0681

Ribbon Cassettes

Black, Re-Inking Cassette 06-0560
Purple, Re-inking Cassette 100-1823

76 Series 70 Maintenance Manual

Description Part Number

Feed Roll Assembly

Feed Roll Assembly 06-2189
Feed Roll Bearing (Two Required) 06-0682
Feed Roll Keeper (C-Clip) 520-9800104

Forms Compensation

Forms Compensation Assembly 09-1484
Forms Compensation Helper Springs 98-1579

Fuse

Fuse 1.0 Amp, 125V 150-9810010
Fuse 1.5 Amp, 125V 150-9810015

Journal Take-Up

Journal Take-Up Motor Assembly 09-1240
Journal Take-Up Spool Assembly 06-0993

Linefeed

Line Feed Stepper Motor 06-1472
Line Feed Idler Gear 06-0542

Miscellaneous

Power Cord, 110V 06-0561
Power Cord, 220V 06-0806
Paper Low Switch Assembly 09-1197
Toggle Switch & Harness Assembly

09-2488

(Long)
Pressure Roll Shaft 09-1872

Paper Supply

Paper Supply Core (Large) 09-1230
Paper Supply Core (Small) 09-1494

3.5 Inch Diameter One-Ply Paper Roll 100-1667

3.5 Inch Diameter Two-Ply Paper Roll 98-0558

6.0 Inch Diameter One-Ply Paper Roll 100-2377

Appendix A: Spare Parts 77

Description Part Number

Printhead

Printhead, 9-Wire 06-0565
Printhead Clamp 06-0571

Ribbon Feed Mechanism

Ribbon Feed Gearbox Assembly 98-2503

Space Motor Assembly and Space
Rack

Space Motor 06-0578
Space Rack 06-1773

Power Transformer

Power Transformer, 110V 98-0857
Power Transformer, 220/240V 98-0858

OPTIONAL AUTO CUTTER PARTS

Description Part Number

Cutter Assembly 09-1232
Cutter Gear-Intermediate 06-0893
Cutter Gear, Motor (Worm Gear) 06-0894
Cutter Gear, Rotary Knife
Listed as above and as Transport, Gears (3

Required)
Cutter Motor Assembly 09-1485
Cutter Shield Gear 06-1107
Cutter Shield (Rotary Knife) 09-1710
Cutter, Rotary Knife 09-1233

06-0892

Cutter, Shear Plate 06-1109
Cutter, Shear Plate Spring 06-0875
Cutter/Transport Assembly 09-1570
Transport, Optical Sensor 09-1576
Transport, Upper Paper Guide (Pin) 09-1565

78 Series 70 Maintenance Manual

Appendix B: Theory of Operation 79

APPENDIX B: THEORY OF
OPERATION

ELECTRICAL OPERATION

CIRCUIT OPERATION

Figure 49: Electrical Circuits of Printer Components

80 Series 70 Maintenance Manual

The electrical section of the printer consists of the components shown in the
illustration on the previous page.

The Control Board contains the Microprocessor and its peripheral circuits, the
DC power circuit, and Printhead and Line Feed Motor drive circuits.

The Interconnect Board contains the Take-Up Motor and Cash Drawer Driver
circuits. It connects the Keypad, Carriage, Line Feed Motor, and Validation
Sensor to the Control Board.

The printer control signals from the host system (PC or termina) are brought
directly to the Control Board from the rear panel on standard printers (parallel
interface). On units with an optional serial interface, the host signals are
brought from the rear panel to a board attached to the Control Board.

INITIALIZATION

The printer is initialized when the power is turned on or when the parallel
interface signal, I-PRIME, is received from the host computer.

Initialization is started with the RSTOUT signal output from the reset circuit
(Q7 pin 13) to reset Q12 (micro-processor), Q4 (interface LSI), and 5 (motor
control LSI).

When resetting is completed, the program starts with mode setting of Q12, Q4,
and Q5, memory (ROM and RAM) check, AM initialization, and then carriage
homing. The program finally establishes the interface signals (output of ACK
signal, BUSY signal, etc.), lights the select indicator, and informs the host
system that the printer is ready for data reception (in the data reception wait
state). This completes the initialization routine.

COMMUNICATION INTERFACE CONTROL

Parallel Interface

Figure 50: Parallel Communication Sequence

Appendix B: Theory of Operation 81

The data from the interface is input through the connector (CN1), and the
interface LSI (Q4: M6990) latches this input data in sync with the /STB signal.

The BUSY signal is on during processing of this data. When the processing is
completed, the BUSY signal is turned off, and an /ACK signal is sent to request
more data.

Serial Interface

Serial Option #1 has its own 8051 processor and memory and converts the
serial input data stream to parallel form. This data is input to the main control
board in the same manner as the parallel interface, except that the data enters
through CN2 instead of CN1 on the Control Board.

With a Serial Option #2 board installed, the ISEL signal goes low, and the
interface LSI changes the I/O port to the serial interface(CN2).

Serial data from the Serial Interface Board is input through pin 33 (NSTB) of
the LSI (Q4). This data is output from pin 44 (NRXD) via the internal latch,
and is sent to serial port pin 10 (RXD) of the microprocessor (Q12).

Serial output data is sent directly from pin 11 (TXD) of the microprocessor.

PRINTHEAD DRIVE CIRCUIT

Figure 51: Communication Sequence of the Printhead Drive Circuit

This circuit drives the head magnets corresponding to the HEAD DATA1 to 9
signals in accordance with the HEAD-ON signal. This makes the print head
print characters.

When the HEAD-ON signal goes high, the RC integrator (R157, and C158 or
C55) determines the head drive time. The integrator lengthens the drive time if
the drive voltage (+30) lowers, and shortens the drive time if the voltage rises.
This maintains consistent print wire impact force.

82 Series 70 Maintenance Manual

CARRIAGE DRIVE

Space Motor Control

Figure 52: Communication Sequence for Space Motor Control

The motor control LSI (Q4) outputs the space motor phase signals (SP-U,
SP-V, SP-W) in accordance with the spacing command from the
microprocessor, and at the same time outputs the overdrive signal (SPD-A).

The SPD-A signal is a fixed-period pulse signal whose pulse width is
controllable by the program, and is used to control the motor drive time.

The SP ON/OFF signal is output during acceleration and deceleration when
greater torque is required.

The motor driver (MTDV) drive the space motor in accordance with these
signals. Pins 9 and 11 of the MTDV are for the over-voltage (9) and over­current (11) protective circuits

.

Slit Encoder

Appendix B: Theory of Operation 83

LINEFEED

Figure 53: Communication Sequence for Slit Encoder

Space motor PHASE-A and PHASE-B signals are generated by a photo-sensor
and a slit disk. The motor control LSI (Q4) frequency divides these edge pulse
signals at a rate dependent upon the print pitch, and outputs the /IPT signal to
provide dot-on and carriage position timing.

Figure 54: Communication Sequence for Linefeed

The Linefeed Motor is locked with the +8 voltage while it is stopped. When line
feeding, the Linefeed motor is driven by the +30 supply in accordance with the
LF OVD signal.

84 Series 70 Maintenance Manual

ALARM CIRCUITS

Drive Circuit Fault Alarm Circuit

This is a protective circuit that makes the AC fuse blow when a fault occurs in
the Printhead Drive Circuit, Space Motor Drive Circuit, Line Feed Motor Drive
Circuit, or their peripheral circuits.

The circuit operates by monitoring the drive time using the HDALM, SPALM,
and LFALM signals interlocked with the overdrive signal of each drive circuit.
If the drive time of any drive circuit exceeds the specified time, the drive circuit
fault alarm circuit outputs an ALM signal (high) to turn on the SCR.

This causes the secondary coil (30V) of the transformer to be short-circuited,
causing an over-current to flow through the primary coil, which then makes the
AC fuse blow.

Head Overheat Alarm Circuit

In order to protect the head coils, this circuit monitors the head temperature
using the built-in thermistor of the printhead.

If heavy-duty printing is performed continuously for a long time, the printhead
temperature rises. When the Printhead temperature reaches approximately 100°
C, a head overheat alarm occurs. At this point, the print mode is switched from
bi-directional to uni-directional to reduce the duty-cycle which in turn lowers
the temperature of the Printhead. When the Printhead temperature returns below
the alarm detection temperature, bi-directional printing is resumed.

When the temperature of the Printhead rises during operation, the resistance of
the thermistor lowers, and the potential of the comparator (Q7) negative input
lowers to invert the comparator’s output, causing the HEAD TEMP signal to
be output to the motor control LSI.

With the turbo option installed, the print may stop completely. The printer will
start back-up again as the temperature falls below the threshold.

Note: This is a normal operation and will not cause any data loss. Do not turn

POWER SUPPLY

The power supply consists of a Power Transformer, Power Supply Board, and
a DC Power Supply Circuit.

the printer off or data loss will result.

The input AC voltage is transformed into 7.6 VAC, 24 VAC, and 10 VAC by
the power transformer. These AC voltages are converted into +8 VDC, +5
VDC, and +30 VDC levels.

Appendix B: Theory of Operation 85

AC Switch Plate

The AC Switch Plate mounts the Power Switch, AC Fuse, and AC Noise Filter.

Power Transformer

If the Power Transformer temperature rises abnormally, the transformer’s built­in temperature fuse blows to prevent adverse effects on other components.

MECHANICAL OPERATION

PRINTHEAD MECHANISM AND OPERATION

The Printhead is spring-loaded, using a permanent magnet, and can be easily
removed or installed. The Printhead is mounted on a Carriage that runs parallel
to the Platen and is connected with the control circuit via the Interconnect
Board.

The Printhead consists of the following items:

♦ Wire Guide
♦ Wires
♦ Armature Assembly
♦ Yoke
♦ Springs
♦ Spacer
♦ Magnet Assembly
♦ Thermistor
♦ PC Board

Printhead Operation

When the Printhead is in the non-printing state, each armature is attracted by
the permanent magnet and the springs holding the armatures are compressed by
the thickness of the spacer. Therefore, the print wires, which are fastened to the
individual armatures, are held retracted within the wire guide.

When signals corresponding to a character to be printed are detected by the
control circuit, currents flow through the corresponding coils to nullify the
magnetic flux generated by the permanent magnet assembly. With the magnetic
flux nullified, the print wire coil armatures are driven toward the Platen by the
force of the armature springs. The print wires, fastened to the armatures, are
ejected from the tip of the wire guide and strike the paper through the ribbon.

86 Series 70 Maintenance Manual

After the character is printed, the magnetic flux of the permanent magnet
assembly attracts the armatures again which retract the print wires back into
the wire guide.

The Printhead has a built-in thermistor to prevent the coils from overheating.

SPACE MECHANISM AND OPERATION

The spacing operation is performed by the DC Motor driving the Carriage
Frame, which is guided by the Carriage Shaft mounted parallel to the Platen.
The DC Motor is mounted on the bottom of the Carriage Frame.

The Space Mechanism consists of the following items:

♦ DC Motor with Motor Gear
♦ Carriage Frame
♦ Carriage Shaft
♦ Space Rack
♦ Slit Sensor
♦ Slit Disk

The Carriage, with the Printhead and Space Motor mounted on it, moves
parallel to the Platen along the Carriage Shaft. As the Space Motor rotates
counterclockwise, the motor gear is driven to the right along the Space Rack,
and as a result, the Carriage is also driven to the right.

The spacing mechanism is designed such that when the Space Motor rotates one
turn, the Carriage Frame moves 0.8 inches (20.32 mm).

Motor rotation also rotates the Slit Disk, and the slits pass through the Slit
Sensor. The position of the Carriage Frame can be obtained by counting the
number of slits detected by the slit sensor.

RIBBON FEED MECHANISM AND OPERATION

The Ribbon Feed Mechanism feeds the Ribbon synchronously with the spacing
operation. The mechanism is driven by the Space Motor.

The Ribbon Feed Mechanism consists of the following items:

♦ Ribbon Feed Gear Assembly
♦ Ribbon Gear (Space Motor)
♦ Ribbon Cartridge

Appendix B: Theory of Operation 87

Ribbon Feed Operation

As the Space Motor rotates, the Ribbon Gear on the Space Motor Shaft rotates
to drive the Drive Gear in the Ribbon Cartridge via the Ribbon Feed Gear
Assembly. As a result, the Ribbon is fed.

In bi-directional printing, the Ribbon Gear rotational direction reverses every
time the Carriage reverses direction. In this case, the gears in the Ribbon Feed
Gear Assembly switch the rotational direction to feed the Ribbon in a fixed
direction.

Ribbon Cartridge

A one-way-feed endless ribbon is used. Ink is replenished by the built-in ink
tank in the ribbon cartridge. This assures clear printing.

PAPER FEED MECHANISM AND OPERATION

The printer feeds paper by rotating the Feed Roller, which is driven by the Line
Feed Stepper Motor through a speed reduction gear. The paper is pinched
between the Feed Roller and the Pressure Shaft on the Forms Compensation
Assembly. This maintains constant pressure regardless of the thickness of the
paper or form.

The Paper Feed Mechanism consists of the following items:

♦ Stepper Motor with Gear
♦ Reduction Gear
♦ Feed Roller
♦ Pressure Roller Shaft

The Paper Feed Stepper Motor is mounted on the right side of the Base Plate,
and its rotation is transmitted to the Feed Roller through the Reduction Gear.
The Feed Mechanism is designed such that when the Stepper Motor rotates 48
steps (360 degrees), paper is fed 0.167 inches (4.32 mm).

PAPER-LOW DETECTION MECHANISM AND OPERATION

When paper is present in the printer, a small lever is prevented from
interrupting the path of a sensor located on the Bucket Assembly. When the
printer runs low of paper, the lever falls and interrupts the optical path of the
sensor, causing a paper low condition. This indicates that there are ten to twelve
feet of paper left.

88 Series 70 Maintenance Manual

Appendix C: Schematics 89

APPENDIX C: SCHEMATICS

The following schematics are provided in this appendix:

♦ Control Board (Revision 10, Part Designator: SLMR)
♦ Serial Board (Revision 12, Part Designator: SLHI)
♦ Interconnect Board (Revision A, Part Designator: 09-1912)

All schematics are for the latest revisions of these boards.

90 Series 50 Maintenance Manual

CONTROL BOARD

Appendix C: Schematics 91

92 Series 50 Maintenance Manual