Various Controls

6.3.1 Controlling the Laser Activation Timing 6.3.1.1 Generating the Sync Signal

0015-4425

iR5065 / iR 5055 / iR5075 / iR5075N / iR5065N / iR5055N

The BD signal used to synchronize the video signal in laser scanning direction is generated by the BD PCB with reference to the laser beam reflected by the BD mirror mounted on the laser beam optical path. The CCD/AP PCB reads the image signal from the CCD, and sends it to the controller block. The controller block, in response, executes image processing, and sends the result as a video signal to the laser driver PCB by way of the video PCB and as the laser intensity control signal to the laser unit.

6.3.1.2 Flow of the Sync Signal

0015-4426

iR5065 / iR 5055 / iR5075 / iR5075N / iR5065N / iR5055N [1] BD signal (upon detection of laser light, '0').

[2] phase matching is executed with reference to the printer, and the synch signal is generated.

[3] reads the image data from the image memory in keeping with the printer sync signal.

[4] video signal

[5] converts the 2-pixel parallel signal into a signal-pixel serial signal.

[6] laser drive signal (drives the laser unit according to the video signal).

F-6-3 ERROR DODE:

E100

Issued when the BD signal is not detected within a specific period of time after the laser has been turned on.

6.3.2 Controlling the Intensity of Laser Light 6.3.2.1 Controlling the Laser Intensity

0015-4427

iR5065 / iR 5055 / iR5075 / iR5075N / iR5065N / iR5055N

Main power switch ON Start key ON

Image leading edge signal(PTOP)

Laser

PRINT INTR

WMUP CNTR WLSTR STBY LSTR STBY

BD signal(BD) Laser scanner

motor(M15)* Half speed Full speed Half speed

Video signal

BD PCB Video PCB

Laser

The laser driver circuit serves to drive the semi-conductor laser with reference to the laser drive signal (LD) coming from the DC controller PCB.

The laser drive circuit is associated with the following items of control:

- laser activation control

- laser intensity control (APC control)

- laser intensity control to suit the drum surface potential The various signals have the following meanings and functions:

[1] sample laser activation signal; for each scan, it turns on the laser for sampling of light intensity (for imaging) [2] laser activation enable signal; after the Start key has been pressed, it goes '0'when the laser is ready for activation.

[3] laser write start signal; when paper reaches the laser write start sensor (PS28) mounted in front of the registration roller, the machine starts laser write oper-ation.

[4] the machine monitors the intensity of laser light upon its activation (for sampling), and feeds the appropriate value to the laser drive circuit.

[5] the machine controls the output so that the value that has been fed and the reference value from the DC controller are identical.

[6] laser intensity reference signal; it serves as the laser activation reference (determined as a result of potential control by the DC controller).

F-6-4 MEMO:

- The laser power is adjusted automatically when the laser unit is replaced.

- When the manual feed tray is used as the source of paper, the write operation starts when the registration paper sensor (PS29) detects paper.

SERVICE MODE:

DISPLAY> DPOT> LLMT

indicates the laser power voltage control value for copier imaging.

DISPLAY> DPOT> LPOWER-P

indicates the result of potential control for the laser intensity used during printer (PDL) imaging.

DISPLAY> DPOT> LPOWER-C

indicates the result of potential control for the laser intensity used during copier imaging.

DISPLAY> MISC> LPOWER indicates the laser intensity in real time.

ADJUST> LASER> PVE-OFST used to adjust the laser incident point.

FUNCTION> LASER> POWER used to turn on laser light.

6.3.2.2 APC Control

0015-4428

iR5065 / iR 5055 / iR5075 / iR5075N / iR5065N / iR5055N

The machine executes APC control so that the laser light will remain at a constant level by adjusting the output of the laser diode mounted on the laser driver.

The control mechanism takes place on the DC control PCB.

The DC controller sends the laser control signal (LD1: CTL0=0, CTL1=1, CTL2=0; LD2: CTL0=1, CTL1=0, CTL2=0; both APC-SEL=0) to the laser driver IC on the laser driver PCB.

In response, the laser driver IC sets APC mode, and forces the laser diode (LD) to emit light.

While all this is under way, the laser driver IC monitors the laser diode (LD) by means of a photo diode (PD), and adjusts the output of the laser diode unit so that the intensity is at a specific level.

DC controller PCB

Laser driver PCB

J1408

J1411

J113

J122 J1401 J4500

LWRPD

F-6-5

6.3.3 Controlling the Laser Scanner Motor 6.3.3.1 Controlling the Laser Scanner Motor

0015-4472

iR5065 / iR 5055 / iR5075 / iR5075N / iR5065N / iR5055N

The machine controls the laser scanner motor so that the motor always rotates at a specific speed.

The control mechanism takes place in the motor speed control block.

The motor speed control block detects the speed detection signal (FG, BD), and compares it against the reference signal generated by the reference signal generation block on the DC controller PCB; it then controls the acceleration signal (ACC) and the deceleration signal (DEC) so that the motor will rotate at a specific speed.

The machine switches over speed detection to suit the current printer state, thereby reducing the time used to control the scanner motor.

The FG signal is a detection signal used for rough adjustment of the motor speed, while the BD signal is a detection point signal used to fine-tune the motor speed.

T-6-3

F-6-6 ERROR CODE:

E110 (scanner motor error)

-0001: after the scanner motor has been started up, the FG signal is not detected within a specific period of time, or while the scanner motor is rotating at a stable speed, the FG signal is not detected.

Start-up startup -> half speed FG control

half speed -> full speed FG -> BD control

STBY half speed FG control

Imaging full speed BD control

Deceleration full speed -> half speed BD -> FG control

half speed -> stop FG control

Laser

Video PCB Laser Driver PCB

Laser Scanner

6.4 Parts Replacement Procedure

6.4.1 Laser Scanner Unit

6.4.1.1 Removing the Laser Scanner Unit

0015-4863

iR5065 / iR 5055 / iR5075 / iR5075N / iR5065N / iR5055N

1) Open the right door unit (upper); then, remove the 1 screw [2] from the door strap, and fully open the right door unit (upper).

F-6-7

2) Slide the developing assembly locking unit [2] in the direction of the ar-row to detach.

- 1 Screw [1]

3) Detach the scanner cover [4].

- 4 Screw [3]

F-6-8 4) Disconnect the 4 connectors [1].

5) Detach the 1 leaf spring [3].

- 2 Screw [2]

6) Hold the front of the laser scanner unit [4], and lift and take out.

F-6-9

6.4.1.2 When Replacing the Laser Scanner Unit

0015-9960

iR5065 / iR 5055 / iR5075 / iR5075N / iR5065N / iR5055N

If the temperature of the fixing assembly is 150 deg C or higher when the main power switch is tuerned on, the machine will not execute potential con-trol. If such is the case after replacing the scanner unit, manually execute po-tential control in service mode as follows:

1) Make the following selections in service mode: COPIER> FUNCTION>

DPC> DPC; then, enter '1', and press [OK].

2) Turn off and then back on the main power switch.

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[2]

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[3] [4] [3]

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[3]

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