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2
UNIT EXPLANATION
3 DIS./ASSEMBLY 2 UNIT EXPLANATION 1 OUTLINE
EXTERNAL SECTION
1 OUTLINE
EXTERNAL SECTION
[1] Composition
Platen cover (Option)
2 UNIT EXPLANATION
Sub power switch Operation panel
(SW2)
Exit tray
Front door
Main power switch
(SW1)
Upper tray
3 DIS./ASSEMBLY
Lower tray
By-pass tray Rear cover
KRDS interface (serial)
DC5V jack
ISW interface (parallel)
ADU door
2-A-1
DRIVE SECTION
1 OUTLINE
DRIVE SECTION
[1] Composition
2 UNIT EXPLANATION
Main motor (M1)
Toner supply motor (M4)
Developing motor (M3)
3 DIS./ASSEMBLY
Paper feed drive
motor (M9)
ADU motor (M6)
[2] Mechanisms
Mechanisms Method
Drum, Conveyance, Gear drive (M1)
Developer agitation,
Fixing, and exit drive,
ADU conveyance drive
Developing sleeve Gear drive (M3)
drive
Paper feed drive, Gear drive (M9)
ADU conveyance drive
Toner supply drive Gear drive (M4)
ADU drive Gear drive (M6)
2-B-1
DRIVE SECTION
1 OUTLINE
[3] M1 (main motor) control 2. Signals
a. Input signals
24VDC 24VDC (1) M1 LOCK SIG (M1 PRDB)
2 24VDC
PGND
24VDC
PGND A monitoring signal for the rotation of M1.
2 UNIT EXPLANATION
PGND PGND
M1 LOCK SIG M1
M1 CLK
Goes [L] when M1 rotation reaches the rated speed.
SGND M1 CONT
5VDC 5VDC [H]: Stopped, or rotating at other than rated speed.
SGND
[L]: Rotating at rated speed. (PLL: stable)
(2) PS3 (PS3 PRDB)
Paper exit passage detect signal.
[H] when paper is detected.
SGND
PS3 PS3
5VDC b. Output signals
DCPS PRDB
(1) M1 CONT (PRDB M1)
3 DIS./ASSEMBLY
M1 drive control signal.
M1 (main motor) is controlled by the PRDB (printer drive [L]: M1 ON
board). [H]: M1 OFF
1. Operation (2) M1 CLK (PRDB M1)
M1 is a brushless motor running on 24VDC, and Reference clock for M1 rotation control.
drives the following: 2nd paper feed, fixing, drum,
toner conveyance screw, toner recycle screw, and
part of developing agitation screw ADU conveyance.
M1 includes an internal speed PS, and utilizes PLL
control to maintain constant speed. Rotational speed
is controlled by a reference clock signal output by
PRDB.
M1 comes ON when the START button is pressed, and
goes OFF at a predetermined time interval after PS3
(exit sensor) goes OFF for the final copy.
At warm-up start, M1 comes ON. only during initial
drum charging.
2-B-2
READ SECTION
1 OUTLINE
READ SECTION
[1] Composition
Home-position
sensor (PS14)
2 UNIT EXPLANATION
Exposure unit
Optics wires APS sensors 1 and 2
(PS17, PS18)
V mirror unit Exposure-lamp
inverter (INV1)
V mirror unit
2nd mirror 1st mirror
3 DIS./ASSEMBLY
Scanner drive
board (SCDB)
3rd mirror Optical motor (M2)
CCD unit (AD converter
board (ADB))
[2] Mechanisms
Mechanism Method
Light source Xenon lamp Slit glass Platen original
Exposure unit
Exposure Light source slit exposure
Scanning * Platen original scanning:
Movement of 1st, 2nd,
and 3rd mirrors.
RADF original scanning: V mirror unit CCD unit
Original is moved with light
source held stationary.
Lamp power supply Lamp cord
RADF original
* Platen and RADF scans operate as follows.
a. Platen original: The original is placed on the platen
glass, and reading is accomplished by movement
of the exposure unit and V mirror unit.
b. RADF original: The exposure unit and V mirror unit
are shifted under slit glass, and the original is
scanned as it passes over the exposure unit.
2-C-1
READ SECTION
1 OUTLINE
[3] M2 (optical motor) control c. Initial operation when power is turned ON
When SW2 (power switch board) comes ON, the
exposure unit starts a home position search. The
search procedure differs according to whether PS14
2 is ON or OFF. Upon completing the search, the
2 UNIT EXPLANATION
24VDC
24VDC U
exposure unit stands by at the platen mode's APS
24VDC V M2 reading position.
PGND W
PGND
PGND (1) When PS14 is turned ON
5VDC
5VDC SGND
SGND PS14 PS14
Shading
SGND 5VDC correction
reading
Platen APS
DCPS SCDB
reading position
Reference
PS14
point
M2 (optical motor) is controlled by the SCDB (scanner
3 DIS./ASSEMBLY
drive board). A related signal is provided by PS14 (optics
home position PS). (2) When PS14 is goes OFF
Shading
1. Operation correction
reading
a. Operation of M2 Platen APS
reading position
M2 is a 3 phase stepping motor running on 24VDC.
This motor drives the exposure unit so as to
Reference PS14
implement scanning. Forward rotation, reverse
point
rotation, and rotation speed are switched as
necessary to carry out each scan cycle.
The exposure unit's home position is detected by
PS14. M2 operation (drive time span and drive
d. Shading correction reading
direction) is controlled by time count after PS14 ON Shading correction read out is implemented using the
or PS14 OFF. white reference plate attached beneath the glass
stopper plate. Shading correction is executed when
b. Exposure unit's scan speed SW2 comes ON.
Scan Speed
e. Exposure scanning modes
Magnification Scan Speed Two modes are implemented: platen mode and DF
Forward 140mm/sec mode.
(1:1 magnification) In platen mode, the exposure unit moves as
Reverse 241mm/sec (max) necessary to scan the original. In DF mode, the
RADF side moves the original while the exposure unit
stays fixed in a specified position (the DF reading
position).
2-C-2
READ SECTION
1 OUTLINE
f. Operation in DF mode (2) Manual copy mode
The DF reading position is to the exit side of PS14.
PS14
The exposure unit moves from its standby position
(the platen APS reading position) to the DF reading
position. Exposure scan
2 UNIT EXPLANATION
It then returns to the platen APS reading position
after completing the original scan and again enters
standby.
Reference Platen APS
point reading position
DF reading Platen APS
position reading position
(3) Book copy (AE) mode
PS14
Reference
PS14
point
AE scan
3 DIS./ASSEMBLY
g. Operation in platen mode
Exposure scan (2nd half)
In this mode, the scan sequence depends on the
copy density selection (either AE or manual).
Exposure scan (1st half)
After completing the scan it returns to the platen APS
reading position.
(1) AE mode
Reference Platen APS
point reading position
PS14
(4) Book copy (Manual) mode
AE scan
PS14
Exposure scan
Exposure scan (2nd half)
Exposure scan (1st half)
Reference Platen APS
point reading position
Reference Platen APS
point reading position
2-C-3
READ SECTION
1 OUTLINE
2. Signals [4] Exposure control
a. Input signal
(1) PS14 (PS14 SCDB)
2 Exposure unit's home position detect signal.
24VDC
24VDC
2 UNIT EXPLANATION
24VDC
PGND
[L]: Exposure unit is in home position. PGND
PGND
[H]: Exposure unit out of home position. 5VDC
5VDC
SGND
SGND
DCPS
b. Output signals
(1) M2 U, V, W (SCDB M2)
M2 (Optical motor) ON/OFF drive signals.
PGND
L1 CONT LV L1
24VDC HV
SCDB INV1 L1INVB
24V
3 DIS./ASSEMBLY
0V
Power for L1 (exposure lamp) is supplied by INV1
(exposure lamp inverter). This action is controlled by the
SCDB (scanner drive board).
1. Operation
L1 is a xenon lamp, and is driven by an inverter
circuit. Since the xenon lamp provides a stable light
intensity with low heat generation, it does not require
light intensity control circuit or overheat protection
circuit.
2. Signals
a. Output signal
(1) L1 CONT (SCDB INV1)
L1 ON/OFF control signal.
[L]: L1 ON
[H]: L1 OFF
2-C-4
READ SECTION
1 OUTLINE
[5] Original reading control 1. Operation
The light from the exposure lamp reflects back from
the original, passes through a lens, and hits the CCD
SGND
sensor. The CCD sensor generates an analog
YCK 1
SGND
electrical signal corresponding to the light intensity.
2 UNIT EXPLANATION
RCK
SGND
The ADB (A/D conversion board) then converts this
YG
SGND
signal into a digital signal.
CLAMP
SGND
SCK
a. Original reading
SIN
SLD The reading timing is as follows.
MD0
MD1
MD2
SGND
(1) Platen mode
OD0
OD1 Reading starts at a predetermined time interval after
OD2
OD3 the START button is pressed and when the exposure
SGND
OD4 unit has moved 6mm in the paper feed direction after
OD5
OD6 CCD PS14 (optics home position) goes OFF.
OD7
SGND
3 DIS./ASSEMBLY
ED0 (2) DF mode
ED1
ED2
ED3 Reading begins at a predetermined time interval after
SGND
ED4 the leading edge of the original causes PS311 (origi-
ED5
ED6 nal registration PS) to come ON.
ED7
APR
12VDC
12VDC
12VDC
12VDC
SGND
5VDC 5VDC
5VDC 5VDC
SGND 5VDC
SGND 5VDC
12VDC SGND
SGND -5VDC
-12VDC -5VDC
SGND -5VDC
12VDC -5VDC
DCPS CB ADB
Original reading is carried out by the CCD sensor on the
ADB (A/D conversion board).
2-C-5
READ SECTION
1 OUTLINE
[6] APS control
L1 is ON during APS detection, so that the illumina-
tion level (light or dark level) in the main scanning dif-
5VDC
fers according to whether the original is present or
2 5VDC
SGND absent. To detect line width (main scanning width),
2 UNIT EXPLANATION
SGND CCD
12VDC the CCD sensor detects the difference from sky shot
SGND
-12VDC black level to paper edge white level at each side. If
SGND
12VDC ADB the RADF is installed, original size detection in the
main scanning is reexecuted when PS304 (DF open/
SGND
PS14 PS14 close PS) comes ON, so as to confirm the original
5VDC
size.
SGND
PS15
5VDC
PS15 The two APS sensors (PS17 and PS18) each consist
of a photosensor and a LED. If the original is present
SGND
PS17 PS17 at the sensor position, the light generated by the LED
5VDC
5VDC reflects from the original and is detected by the
5VDC SGND
SGND PS18 PS18 photosensor.
SGND 5VDC
3 DIS./ASSEMBLY
DCPS SCDB
Exit
side
APS detection is carried out at opening or closing of the
RADF cover or original cover, and is controlled by the PS17 PS18
SCDB (scanner drive board) based on signals from the
APS sensors and CCD sensor. Related signals are
provided by PS14 (optics home position PS), PS15 (APS
timing PS) and by PS304 (DF open/close PS) on the
RADF. : Photosensor
: LED
1. Operation
a. APS detect operation (2) DF mode
APS detection operation differs according to whether Original size detection is carried out by ON/OFF
operation is in platen mode or DF mode. action of PS306 (original size detect PS 1), and
PS307 (original size detect PS 2), and by the
(1) Platen mode resistance level of VR301 (original size detect VR)
Size is detected by the combination of the ON/OFF located in the RADF paper feed tray.
action of PS17 (APS sensor 1) and PS18 (APS
sensor 2) and the detect signal from the CCD sensor
on the ADB (A/D conversion board).
PS17 and PS18 detect the original size in the sub
scanning direction, while the CCD sensor detects the
size in the main scanning direction.
2-C-6
READ SECTION
1 OUTLINE
The following table shows the relation between the 2. Signals
PS sensors and detected original sizes.
a. Input signals
Sensor PS17 PS18
(1) PS15 (PS15 SCDB)
PS306 PS307
RADF cover or platen cover open/close detect signal.
Original Size
2 UNIT EXPLANATION
A3 Original detected Original detected [L]: ON (Execute APS)
(ON) (ON) [H]: OFF (Cancel APS)
B4 Original detected Original detected
(2) PS17 (PS17 SCDB)
(ON) (ON)
Original size detect signal.
A4R Original detected Original not detected
[L]: Original detected.
(ON) (OFF)
B5R Original not detected Original not detected [H]: Original not detected.
(OFF) (OFF) (3) PS18 (PS18 SCDB)
A4 Original not detected Original not detected Original size detect signal.
3 DIS./ASSEMBLY
(OFF) (OFF)
[L]: Original detected.
B5 Original not detected Original not detected
[H]: Original not detected.
(OFF) (OFF)
b. APS detection timing
APS detection timing differs according to whether
operation is in platen mode or DF mode.
(1) Platen mode
Detection is carried out when PS15 (APS timing PS)
comes ON.