Canon LBP-2000, Руководство по обслуживанию

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CHAPTER 2
OUTLINE OF OPERATION
1 . The roles played by specific functions, the relationship between electrical system and me-
chanical system, and the timing at which each mechanism is driven are discussed according
to functions.
In any diagram, the symbol indicates a mechanical path. If a signal name is
given together with the symbol , the flow of a single electric signal is indicated, while
the symbol indicates the flow of multiple electric signals.
2 . In any digital circuit, the level of an electric signal is indicated as follows: if high, using the
letter H or without a slash (/); if low, using the letter L or with a slash (e.g., /SCNON).
If a signal is shown as being H or without a slash, the signal is true (generated) in the
presence of a supply voltage level; it is false (not generated) in the absence of a voltage (i.e.,
GND level). The opposite is true of a signal shown as being L or preceded by a slash.
The Printer uses a microprocessor, but its mechanisms are omitted from discussions, as
they cannot be checked in the field.
In addition, PCBs are not to be repaired in the field, and explanations of circuitry are
limited to outlines using block diagrams. Explanations may cover either from sensors to
inputs of major PCBs or from outputs of major PCBs to loads; or, they are limited to block
diagrams prepared according to functions.
I . BASIC OPERATION ......................... 2 - 1
II. ENGINE CONTROL SYSTEM ....... 2 - 7
III. LASER/SCANNER SYSTEM ......... 2 - 3 0
IV.
IMAGE FORMATION SYSTEM .... 2 - 3 7
V. PICKUP/FEEDING SYSTEM ........ 2 - 4 6
VI. VIDEO CONTROL SYSTEM .......... 2 - 5 9
VII. PAPER FEEDER ............................... 2 - 6 5