HP Enterprise CP5525 manual ITB unit presence detection, ITB cleaning mechanism

The primary transfer roller engagement and disengagement control engages the ITB with the photosensitive drum, or disengages the ITB from the drum, depending on the requirements of the print job.

●All rollers disengaged: The ITB disengages from all four photosensitive drums. This is the state during a standby period, and also is the home position for the primary transfer rollers.

●All rollers engaged: The ITB engages with all the four photosensitive drums. This is the state for full-color jobs.

●Only black roller engaged: The ITB engages with only the black photosensitive drum. This is the state for the black-only print jobs.

The operational sequence of the primary transfer roller engagement and disengagement control is as follows:

1.The fuser motor drives the primary transfer disengagement solenoid to rotate the primary transfer disengagement cam.

2.As the cam rotates, the YMC slide plate or the Bk slide plate moves to right or left. This causes the primary transfer roller to move up or down.

3.The ITB engages with or disengages from the photosensitive drum depending on the movement of the primary transfer rollers.

The DC controller determines that an abnormal primary transfer roller disengagement error has occured and notifies the formatter. This error happens when the DC controller does not detect a specified signal from the primary transfer disengagement switch, even though the primary transfer disengagement solenoid is driven.

ITB unit presence detection

The DC controller detects the ITB unit presence by monitoring the primary transfer disengagement switch. The DC controller drives the primary transfer disengagement solenoid for specified times during the initial rotation period of the following:

●The product is turned on

●The product exits Sleep mode

●The door is closed

The DC controller determines an ITB unit absence and notifies the formatter when it does not detect a specified signal from the primary transfer disengagement switch.

ITB cleaning mechanism

The cleaning blade in the ITB cleaner scrapes the residual toner off the ITB surface. The ITB motor drives the residual toner feed screw and the screw deposits the residual toner in the toner collection unit.

The DC controller detects whether the toner collection unit is full by monitoring the ITB residual toner full sensor. When the DC controller determines the toner collection unit is full, it notifies the formatter. The

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