[7] OPERATION DESCRIPTIONS
7-1. Optical system
1. General descriptions
•
The optical system is composed of the fixed focus lens and six
mirrors.
Since the fixed focus lens is employed, No.4/No. 5 mirror base is
moved as well as the lens to change the distance between the
document and the drum (OID, Original Image Distance) for reduc-
tion and enlargement.
To move the lens and No.4/No. 5 mirror unit, the stepping motor is
driven by the signal from the main control PWB to allow zooming
of 0.70 to 1.41 with 1% increment.
•
Exposure is adjusted by changing the voltage of the copy lamp.
The optical unit is provided with the AE sensor for detection of the
original density to adjust the light quantity of the copy lamp accord-
ing to the original density.
•
For exposure, the slit exposure system is employed where the light
source is moved. (The original table is fixed.)
1
2
9
13
7
6
15
17
12
11
3
16
4
5
10
14
8
OPC drum
1
Copy lamp
2
Reflector
3
No. 1 mirror
4
No. 2 mirror
5
No. 3 mirror
6
Lens
7
No. 4 mirror
8
No. 5 mirror
9
No. 6 mirror
F
No. 2/No. 3 mirror unit
G
Copy lamp unit
H
No. 4/No. 5 mirror unit
I
Mirror motor
J
Lens/No. 4/No.5 mirror unit drive motor
K
Lens home position sensor
L
Mirror home position sensor
M
Auto exposure sensor
(1) Original table
The original table is fixed, and originals are set to the left frame side
as the reference.
(2) Copy lamp
100V system (200W)
200V system (200W)
(3) Mirror
Six mirrors are used.
No. 1 mirror is provided in the copy lamp, No. 2/3 mirrors at the
No.2/3 mirror unit, No. 4/5 mirrors at the No. 4/5 mirror unit. The
No.2/3 mirror unit is scanned during copying. The No.4/5 mirror unit
is moved to change the distance between the original and the
photoconductor during zoom copying.
(4) Lens (Fixed focus lens)
•
Construction (One group 3 lenses)
•
Brightness
(F8)
•
Focus
(174mm)
(5) Lens home position sensor (LHPS)
This sensor is used to sense the lens position. The sensor output
signal serves as the basic signal to control the copy magnification
ratio.
(6) Lens base
The lens is mounted to this lens base. It is moved in the paper feed
direction in reduction copying, and in the paper exit direction in enlar-
gement copying.
7 – 1
www.freeservicemanuals.info
1/11/16
Published in Heiloo, Holland.