Epson 680Pro Service Manual - Page 36

EPSON Stylus COLOR 680/777/77i

Revision B

Operating Principles

Overview

36

Figure 2-9.

Disengage & Clutch mechanism

The Clutch mechanism transmits the PF motor drive to the LD roller shaft only when

the Clutch gear rotates CW direction after the Change lever releases the Clutch lever. If

the Clutch gear rotates CCW direction, the PF motor drive is not transmitted to the LD

roller. This is due to the combination of the shape of the Clutch gear and the Clutch

lock tooth such as described on the figure.

1.

When the paper is advanced with the PF roller, the Change lever is set on the

Clutch lever and the Clutch is pushed down as above Step1’s figure. As the

result, the Clutch gear (*1) is released from the Cluck lock tooth and the drive

from the PF motor is not transmitted to the LD roller shaft.

2.

When the PF pinion gear rotates CCW direction in the above Step2’s figure, the

Change lever moves to the left direction with the CCW rotation of Combination

gear 37.6, 44.4. The Clutch turns back to the engagement position by the tension

force of the Tension spring 0.143 and the Clutch gear is engaged with the Clutch

lock tooth as above Step2’s center figure.

3.

When the PF pinion gear rotates CW direction in the above Step3’s figure, the

Change lever moves to the right direction with the CW rotation of the

Combination gear 37.6, 44.4. And the drive from the PF motor is transmitted to the

LD roller shaft via Clutch gear and Clutch lock tooth.

4.

The LD roller shaft rotates about 360 degree and the Change lever push the Clutch

lever and the PF motor drive is interrupted. This position is the ASF home

position.

Paper Return Plate (Pad holder)

Unlike the previous products, The Paper return plate is built in the ASF frame instead

of the Paper return lever. The Paper separation pad is also stacked on the plate.

It works with the spring force of the Torsion spring 25.7 (mounted in the ASF frame)

as following figure.

Figure 2-10.

Paper Return Plate

The Paper return plate is set to return the paper to the paper stand-by position in the

ASF unit when the ASF unit is in the standby mode. When the paper is fed with the

LD roller, the Paper return plate is stored in the ASF frame by the LD roller.

Following figures show you the ASF paper loading sequence and the operation of the

each mechanism.

Change Lever

Clutch gear

Clutch

Step1

Step2

Step3

Clutch lever

Clutch lock tooth

Tension spring 0.143

LD roller shaft

Spur gear 35.2

NOTE:

The Clutch gear is molded on

the back side of the Spur gear

35.2 such as Combination gear.

LD roller

ASF frame

Torsion spring 25.7

Paper Return

Plate

Hopper

Compression spring 4.80

Section	Page
PRODUCT DESCRIPTION	9
1.1 FEATURES	10
1.2 SPECIFICATIONS	11
1.2.1 Physical Specification	11
1.2.2 Printing Specification	11
1.2.3 Paper Feeding	12
1.2.4 Input Data Buffer	12
1.2.5 Electric Specification	12
1.2.6 Environmental Condition	13
1.2.7 Reliability	13
1.2.8 Safety Approvals	13
1.2.9 Acoustic Noise	13
1.2.10 CE Marking	13
1.3 INTERFACE	14
1.3.1 Parallel Interface (Forward Channel)	14
1.3.2 Parallel Interface (Reserve Channel)	17
1.3.3 USB Interface	18
1.3.4 Prevention of Data Transfer Time-out	19
1.3.5 Interface Selection	19
1.3.6 IEEE1284.4 Protocol	19
1.4 OPERATOR CONTROLS	20
1.4.1 Operating Switch	20
1.4.2 Control Panel	20
1.4.2.1 Switches	20
1.4.2.2 Indicators	20
1.4.3 Panel Functions	21
1.4.4 Printer Condition and Panel Status	22
1.4.5 Printer Initialization	22
1.4.6 Errors	23
1.5 PAPER	24
1.5.1 Paper Handling	24
1.5.2 Paper Specification	24
1.5.2.1 Cut Sheet	24
1.5.2.2 Transparency, Glossy Paper	24
1.5.2.3 Envelope	24
1.5.2.4 Index Card	25
1.5.3 Printing Area	26
1.5.3.1 Cut Sheet	26
1.5.3.2 Envelopes	27
1.6 INK CARTRIDGE	28
1.6.1 Black Ink Cartridge	28
1.6.2 Color Ink Cartridge	28
Operating Principles	29
2.1 Overview	30
2.1.1 Printer Mechanism	30
2.1.2 Printhead	31
2.1.2.1 Printing Process	32
2.1.2.2 Printing Method	32
2.1.3 Carriage Mechanism	33
2.1.4 Paper Feeding Mechanism	34
2.1.5 Paper Loading Mechanism (ASF Unit)	35
2.1.6 Ink System Mechanism	38
2.1.6.1 Pump Unit & Wiper mechanism	38
2.1.6.2 Capping Mechanism	39
2.2 Electrical Circuit Operating Principles	40
2.2.1 C383 PSB/PSE board	40
2.2.2 C383 MAIN Board	43
2.2.2.1 Main elements	44
2.2.2.2 Printhead Driver Circuit	45
2.2.2.3 PF Motor (PF/ PUMP/ ASF Motor) Driver Circuit	46
2.2.2.4 CR Motor Driver Circuit	46
2.2.2.5 Reset Circuit	47
2.2.2.6 EEPROM Control Circuit	47
2.2.2.7 Sensor Circuit	48
Troubleshooting	49
3.1 Overview	50
3.2 Troubleshooting with LED Error Indications	51
Disassembly and Assembly	61
4.1 Overview	62
4.1.1 Precautions	62
4.1.2 Tools	63
4.1.3 Work Completion Check	64
4.2 Disassembly	65
4.2.1 Housing removal	66
4.2.2 Operation Panel removal	67
4.2.3 Printhead removal	68
4.2.4 CR motor removal	71
4.2.5 Waste drain ink pad unit removal	73
4.2.6 Circuit board removal	75
4.2.7 LD Roller removal	79
4.2.8 HP/PE Sensor removal	83
4.2.9 Ink system unit removal (Cap & Pump unit )	85
4.2.10 Paper Eject Roller removal	87
4.2.11 PF motor removal	89
4.2.12 CR unit removal	91
4.2.13 Paper feed roller removal	94
4.2.14 Disassembling ASF frame unit	97
Adjustment	100
5.1 Overview	101
5.1.1 Required Adjustment	101
5.1.2 Adjustment Program feature	102
5.1.3 Adjustment Program Installation Procedure	103
5.1.4 Adjustment Program Initial Setting menu	103
5.1.5 Head ID Input	103
5.1.6 Bi-D Adjustment	105
5.1.7 USB ID input	107
5.1.8 Head Cleaning Operation	109
5.1.9 Initial Ink Charge Operation	110
5.1.10 Refurbishment for DOA	111
5.1.11 Protection Counter Check/Reset	112
5.1.12 Check pattern printing	114
5.1.13 EEPROM check function	115
5.1.14 CSIC Information	116
Maintenance	117
6.1 Overview	118
6.1.1 Cleaning	118
6.1.2 Service Maintenance	119
6.1.3 Lubrication	119
Appendix	123
7.1 Connector Summary	124
7.1.1 Major Component Unit	124
7.1.2 EEPROM Address Map	127
7.2 Component Layout	131
7.3 Exploded Diagram	133
7.4 Parts List	138

Epson 680Pro Service Manual - Page 36

EPSON Stylus COLOR 680/777/77i, Revision B, Operating Principles, Overview,

Page 36 highlights