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6)

Automatic detection of original paper size

• Opening the platen cover by approx. 30 degrees to insert the original, the

platen cover angle sensor turns on and four original size detection sensors
operate simultaneously.

• The original size detection sensors consists of light emission unit and light

reception unit. The light from the light emission unit is thrown on the original
and the reflected light is received by the light reception unit to check the existence
of the original.

• The original size is read again by turning on the platen open/close detecting

sensor when closing the platen cover.

• The automatic original size detecting operation is released when pressing

"original size selector" key in the control panel, setting the original in ADF or
selecting "0" for F5-52.

( Original size detection matrix )

\

– 

Detect

[

– 

No detect

7)

Adjusting quantity of light of AE sensor

• In pre-scan, the output of the AE sensor must be at a proper level. Therefore,

when operating image density control (Quantam

TM 

Technology), the exposure

lamp voltage is adjusted to be approx. 2.7V of AE sensor output when reading
the standard density mark, and the system memorizes the compensation
value at that time.

• In pre-scan automatic exposure mode, the original reflects the light of the

exposure lamp voltage adding the above compensation value, and the original
density is read by the AE sensor. The result corrects the exposure before
copying.

8)

Other operations

• For photo mode, the quantity of light of the exposure lamp is automatically

reduced because the electric potential on drum surface falls.

• The optics unit uses a themostat to prevent the temperature from reaching

abnormally high temps by turning OFF the exposure lamp if it goes above the
specified temperature.

Reference: Service mode for adjustment (for details refer to the volume "Service")

F6-01: Compensation of vertical copy ratio (compensating scanning speed of

optics unit)

F6-02: Compensation of full size focus
F6-03: Compensation of horizontal copy ratio (compensating lens position)
F6-05: Compensation of paper registration position (Compensating timing roller

clutch turning on timing)

F6-11: Compensation of quantity of exposure light for full size
F6-12: Compensation of quantity of exposure light for photo mode
F6-16: Compensation of quantity of light for AE sensor

AOS1

AOS3

AOS2

AOS4

Original  size

Original   size

Original  size

Original  size

detect  sensor(1)

Detect sensor (2) detect semsor  (3) detect semsor (4)

AOS1

AOS2

AOS3

AOS4

Ledger/A3

\

\

\

\

Legal/B4

\

\

[

\

Letter/A4

\

\

\

[

Letter-R/A4R

\

[

[

\

Invoice/A5

\

[

[

[

No original

[

[

[

[

Sub Assemblies

3-33

(8)

Automatic duplex unit (ADU)

1)

Component location

1. Paper pass sensor A
2. Paper width guide
3. Connector
4. ADU tray detecting sensor
5. Paper width guide home position

sensor

6. Paper pass sensor
7. Paper detecting sensor
8. Paper weight lever
9. Pinch roller

10. Transfer guide 2
11. Transfer guide 1
12. Paper feed roller
13. Storage roller

14. Paper weight lever
15. Drive motor
16. Magnetic clutch
17. Clutch gear
18. Paper width guide motor
19. Paper length guide motor
20. DFP pad
21. DFP roller
22. Sensor lever
23. Paper feed tray
24. Transfer roller
25. Paper length guide home position

sensor

14

13

12

13

14

10

11

24

25

26

23

22

19

18

17

9

8

1

2

3

9

21

20

5

7

6

15

16

4

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2)

Mechanical operation

1 Paper stack/paper return operation

When the drive motor rotates counterclockwise and turns gear 6 and the

timing pully, the transfer roller rotates and paper is transported onto the

transfer guide 2. At the same time the magnetic clutch turns ON and the

storage roller rotates, paper is reversed and stored in the ADU.

2 Paper feed operation

When the drive motor rotates clockwise, and turns clutch gear 4, the lift cam

rotates and lifts lift plate 2 by a pressure spring.

Also, the lift shaft and lift plate 2 are driven by the movement of the lift plate 2

and the ADU tray rises.

After lifting up the ADU tray, the magnetic clutch turns ON and the paper feed

roller rotates counterclockwise for feeding paper into the copier.

Magnetic
clutch

Motor pulley

Transport
roller

Gear 3

Gear 6

Lifting Cam

Gear 2

Drive motor

Paper feed
roller

Storage roller

Paper feed roller

Lifting Cam

Clutch gear

Clutch spring

Lifting plate 2

Lifting shaft

Paper feed tray

Lifting plate 1

Pressure Spring

Pulley

Clutch gear

Storage roller

Sub Assemblies

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3 Paper width guide operation

When the paper width guide motor rotates and turns the timing belt, the
paper width guides align paper.

Operation timing for the paper width guide is shown below.

1)When the power switch turns ON:

Move to Letter-R/A4R size position, after
detecting paper width guide home
position sensor.

                                          (Move back +3mm of Letter-R/A4R size : 6 mm play)

2)When copy starts: Move to the selected paper size

(Move back to +3mm of selected paper size : 6 mm play)

3)When stack paper: Move to the selected paper size for align paper.

(Once for every sheet entering)

4 Paper length guide operation

When the paper length guide motor rotates and turns timing belt, the paper
length guide is moved to align paper.

Operation timing for paper length guide is shown below.

1)When the power switch turns ON:

Move to Letter-R/A4R size, position after,

detecting paper length guide home position
sensor.
(Move back to +2.5 mm of Letter-R/A4R size)

2)When copy starts: Move to the selected paper size

(Move back to +2.5 mm of selected paper size)