Canon NP6330 Service Manual page 7

CHAPTER 3 EXPOSURE SYSTEM
I. BASIC OPERATION ...........................3-1
A. Varying the Reproduction Ratio.....3-1
II. LENS DRIVE SYSTEM ......................3-2
A. Movement of the Lens...................3-2
1. Outline ......................................3-2
2. Lens Motor Drive Circuit...........3-4
3. Focusing ...................................3-5
III. SCANNER DRIVE MECHANISM .......3-6
A. Driving the Scanner.......................3-6
1. Outline ......................................3-6
2. Scanning Motor Control Circuit..3-7
3. Relationship between Scanner
Sensor and Signals ..................3-10
4. Sequence of Scanner
Movements (Enlarge/Reduce) ..3-10
5. Sequence of Scanner
Movements (page separation
mode, 2 copies)........................3-11
IV. OTHERS.............................................3-13
CHAPTER 4 IMAGE FORMATION SYSTEM
I. PROCESSES .....................................4-1
A. Outline ...........................................4-1
B. Basic Sequence of Operations
(image formation) ..........................4-2
C. Controlling the Scanner Lamp.......4-3
1. Outline ......................................4-3
2. Turning On and Off the
Scanning Lamp ........................4-4
3. Detecting the Activation of the
Scanning Lamp ........................4-4
4. Protection Mechanism..............4-4
D. Controlling the Primary/
Transfer Corona Current
and the Grid Bias ..........................4-5
1. Outline ......................................4-5
2. Controlling the Primary/Transfer
Corona Current.........................4-6
3. Keeping the Primary/Transfer
Corona Current at a Specific
Level .........................................4-7
4. Turning On and Off the
Grid Bias...................................4-8
E. Controlling the Static Eliminator
Bias/Fixing Roller Bias ..................4-9
1. Outline ......................................4-9
2. Turning ON/OFF the Static
Eliminator Bias/Fixing Bias.......4-10
3. Switching the Output of the
Static Eliminating Bias..............4-10
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A. Controlling the Detection of
Original Sizes.................................3-13
1. Outline ......................................3-13
2. Operation..................................3-15
3. Identifying the Size of Originals ..3-16
4. Identifying the Size of Originals
by the Document Feeder..........3-17
V. DISASSEMBLY AND ASSEMBLY......3-19
A. Scanner Drive Assembly ...............3-19
1. Removing the Scanner Motor ..3-19
2. Outline of the Scanner
Drive Cable...............................3-20
3. Removing the Scanner
Drive Cable...............................3-21
4. Routing the Scanner Cable ......3-26
B. Lens Drive Assembly.....................3-30
1. Removing the Lens Motor ........3-30
2. Attaching the Lens Drive Belt...3-31
3. Removing the Lens hood ..........3-32
4. Preventing Separation Faults
(thin paper picked up from
the multifeeder) .......................4-10
F. Controlling the Developing Bias ....4-11
1. Outline ......................................4-11
2. Turning On and Off DC
Component of the Developing
Bias and Controlling the
Voltage Level............................4-12
3. Turning On and Off the AC
Component of the
Developing Bias .......................4-13
4. Sequence of Operations
(developing bias) .....................4-13
G. Controlling Blank Exposure ...........4-14
1. Outline ......................................4-14
2. Operation..................................4-15
3. Controlling the Slide Shutters...4-15
H. Mesuring the Density of
Originals ........................................4-16
1. Outline ......................................4-16
2. Operation..................................4-17
3. AE Adjustment..........................4-18
I. Cleaning the Transfer Charging
Wire ...............................................4-19
1. Outline ......................................4-19
2. Operation..................................4-19
II. DEVELOPING ASSEMBLY/
DRUM CLEANER...............................4-21
CANON NP6330 REV.0 MAY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)