Controls
Drum Unit
The drum unit mainly consists of the photosensitive drum, primary charging roller, brush roller, cleaning blade, and waste toner feed screw, and is driven by the main motor (M1).
Cleaning blade in contact with the photosensitive drum scrapes off the residual toner on its surface without being transferred to a paper. The residual toner scraped off by the cleaning blade is fed from the toner ejection part into the waste toner box by the waste toner feed screw. The primary charging roller is cleaned by the brush roller in contact with it.
M1
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Main motor
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[1]
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Main motor drive signal
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Primary Charging Bias Control
The machine is directly charged by the charging roller. DC bias and AC bias that stabilized the charge is applied to the primary charging roller.
[1]
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Primary charging bias control signal
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[2]
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Environment sensor detection signal
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Constant voltage control of DC bias and AC bias
The DC bias and AC bias control circuits on the DC controller PCB control the DC bias and AC bias applied to the primary charging roller to keep their voltage at the fixed level.
DC bias switch control
The DC bias output varies according to the environment detected by the environment sensor (HU1).