Canon NP6218 Service Manual page 76

IMAGE FORMATION SYSTEM
This chapter discusses the principles of how images are formed. It also explains the timing at
which the various units involved in image formation are operated, and shows how they may be
disassembled/assembled and adjusted.
I. PROCESSES .....................................4-1
A. Outline ...........................................4-1
B. Basic Sequence of Operations
(image formation system)..............4-3
C. Controlling the Scanning Lamp .....4-4
D. Controlling the Primary Charging
Roller Bias .....................................4-10
E. Controlling the Transfer Roller
Bias................................................4-13
F. Controlling the Static Eliminator
Bias................................................4-16
G. Controlling Blank Exposure ...........4-18
H. Controlling the Primary Corona
Roller Cleaning Mechanism ..........4-20
I. Releasing the Transfer Roller ........4-21
COPYRIGHT © 1997 CANON INC.
CHAPTER 4
CANON NP6218 REV. 0 MAY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
II. DEVELOPING ASSEMBLY AND
CLEANING ASSEMBLY .....................4-22
A. Outline ...........................................4-22
B. Controlling the Toner Level
Detection .......................................4-23
C. Controlling the Development
Bias................................................4-25
D. Automatic Control of Copy
Density...........................................4-27
III. DISASSEMBLY AND ASSEMBLY ......4-30
A. Illumination Assembly....................4-30
B. Drum Unit ......................................4-39
C. Primary Corona Assembly.............4-41
D. Transfer Charging Assembly .........4-44
E. Developing System........................4-47