Canon iR2200 Series, Руководство по обслуживанию

Страница: 185 / 768

COPYRIGHT © 2001 CANON INC. 2000 2000 2000 2000 CANON iR2200/iR2800/iR3300 REV.0 MAR. 2001
CHAPTER 4 IMAGE FORMATION SYSTEM
4-5 P
2.2 Turning On/Off the Bias
The primary charging roller bias is turned on/off as follows:
2.2.1 DC Bias
[1] When the primary charging output enable signal from the DC controller PCB goes ‘0’,
the DC bias output control signal (pulse signal) is generated.
[2] The DC bias is sent to the primary charging roller.
2.2.2 AC Bias
[1] When the primary charging output enable signal from the DC controller PCB goes ‘0’,
the AC bias output control signal is generated.
[2] The AC bias is generated to the primary charging roller.
2.3 Controlling the Current Voltage/Current to a Specific Level
The output level of the DC/AC bias applied to the primary charging roller is controlled by
the DC/AC bias output control signal from the PW-CPU.
2.3.1 Controlling the DC Bias to a Specific Level
[1] The output voltage level of the DC bias is fed back to the PW-CPU, and the DC bias
output control signal is varied as needed to suit the level when driving the transformer.
[2] The DC bias is made to assume a specific voltage level.
2.3.2 Controlling the AC Bias to a Specific Current Level
[1] The output current level of the AC bias is communicated to the drive control circuit and
is compared against the reference current level; the result is used to vary the AC bias
output control signal as needed to drive the transformer.
[2] The AC bias is made to assume a specific current level.