Controlling The Pre-Transfer Charging; Outline; Controlling The Output To Suit The Environment (Fuzzy Control) - Canon Image Reader-A1 iR5000i Service Manual

3.4 Controlling the Pre-Transfer Charging

3.4.1 Outline

The system used for pre-transfer charging serves the following functions:
1. Controlling the DC bias to a specific level of current.
2. Controlling the AC bias to a specific level of voltage.

3. Controlling the output to suit the environment (fuzzy control).

The system used to control the pre-transfer charging is constructed as follows:
J510A
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PT/SP-LEAK-DETECT [1]
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PT/SP-CNT [2]
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PT/SP-REMOTE [3]
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The following signals are used:
[1] pre-transfer/separation charging leakage detection signal: '0' when an excessively high
or low level of current is detected.
[2] pre-transfer charging control signal; the output of pre-transfer current turns ON when
the voltage is about 3 V or more and less than 11 V; it turns OFF when the voltage is
about 12 V or more.
[3] pre-transfer/separating charging remote signal; turns on/off the output of the pre-trans-
fer/separation current.
COPYRIGHT © 2001 CANON INC.
J4502
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F04-304-01
2000 2000 2000 2000 CANON iR5000i/iR6000i REV.0 JUNE 2001
CHAPTER 4 IMAGE FORMATION SYSTEM
The level of current of the
pre-transfer bias varies as follows
in keeping with the potential of
PT-SP-CNT.
-300µA
PT/SP-CNT
Pre-transfer charging wire
J4505
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2
3V 11V12V
AC+DC
T4501
4-23 P