Ricoh A318 User manual

DOCUMENT FEEDER

1. SPECIFICATIONS
Original Size and Weight: – Thin original mode –
Maximum A3/11" x 17"
Minimum B6/51/2" x 81/2"
Weight 41 to 128 g/m2(11 to 34 lb)
– Thick original mode –
Maximum A3 / 11" x 17"
Minimum B6 / 51/2" x 81/2"
Weight 52 to 128 g/m2(14 to 34 lb)
– Auto reverse mode –
Maximum A3 / 11" x 17"
Minimum B6 lengthwise /
51/2" x 81/2" lengthwise
Weight 53 to 105 g/m2(14 to 28 lb)
Original Feed: Automatic feed — ADF mode
Manual feed one by one — SADF mode
Original Table Capacity: 35 sheets / 64 g/m2(17 lb)
Original Set: Face up. First sheet on top
Original Transport: One flat belt
Copy Speed: 20 copies/minute for A4/81/2" x 11" sideways
Power Consumption: 20 W
Dimensions (W x D x H): 670 x 460 x 103 mm (26.4" x 18.1" x 4.1")
Weight: Approximately 9.0 kg (19.916 lb)
Document
Feeder
1 May 1993 SPECIFICATIONS
1

2.COMPONENT LAYOUT
– Mechanical Components –
1.PulseGenerator Disk 6. Inverter Pawl
2. Friction Belt 7. Inverter Roller
3.Pick-upLever8. Transport Belt
4. Original Table 9. Pick-up Roller
5. Exit Roller 10. Feed Roller
– Electrical Components –
1. Original Set Sensor 9. DF Main Board
2.RegistrationSensor 10. Feed-outMotor
3.PulseGenerator Sensor 11. Inverter Solenoid
4.Original Width Sensor 12. Feed-outSensor
5.Pick-upSolenoid 13. Original Select Switch
6.BeltDriveMotor 14. Feed-inSolenoid
7.Indicator Panel 15. DF PositionSensor
8. Lift Switch (A054, A072, A111 copiers only)
123 456
789
10
1
2
34567
9
10
13
14 12
8
11
15
COMPONENTLAYOUT 1 May1993
2

3. ELECTRICAL COMPONENT DESCRIPTIONS
Symbol Name Function Index No.
Motors
M1 Belt Drive Motor DC servomotor that drives to the transport belt
and feed-in system (pick-up roller, feed roller,
pull-out roller and relay roller).
6
M2 Feed-out Motor DC servomotor that drives the feed-out unit of
the DF. 10
Solenoids
SOL1 Pick-up Solenoid Energizes to press the pick-up lever against
the stack of originals in preparation for original
feed-in.
5
SOL2 Feed-in Solenoid Turns on to engage the feed-in clutch so
rotation is transmitted to the feed roller,
pull-out rollers, and relay rollers.
14
SOL3 Inverter Solenoid Energizes to invert the original when copying
two sided originals. 11
Switches
SW1 Lift Switch Informs the CPU when the DF is lifted and
also serves as the jam reset switch for the DF. 8
SW2 Original Select
Switch Selects thick original mode or thin original mode. 13
Sensors
S1 Original Set
Sensor Informs copier CPU that originals have been placed and causes the Insert Original
indicator to go out.
1
S2 Registration
Sensor Sets original stop timing and measures original length. 2
S3 Original Width
Sensor Determines the width of the originals. 4
S4 Pulse Generator
Sensor Generates pulses used to measure the original length. 3
S5 Feed-out Sensor Checks for original misfeeds and sets original
stop timing when in auto reverse mode. 12
S6 DF Position Sensor Detects when the document feeder is
positioned about 10 cm above exposure
glass. (A111 copier only)
Printed Circuit Boards
PCB1 DF Main Board Controls all DF functions. 9
PCB2 Indicator Panel
Board Contains operator indicators. 7
Document
Feeder
1 May 1993 ELECTRICAL COMPONENT DESCRIPTIONS
3

4. OVERALL MACHINE CONTROL
The DF CPU monitors the input signals from the sensors and switches, and
energizes the solenoids and the indicator LEDs directly. The belt drive motor
and the inverter motor are controlled by the DF CPU through their respective
driver ICs. The exchanged signals are shown in the tables on the next page.
DF Main Board (PCB1)
RXD
TXD
Copier Main Board (PCB1)
CPU
ROM
Driver
IC
Driver
IC
TXD
RXD
Feed-out
Motor
Belt Drive
Motor
Solenoids
Indicators
Sensors
Switches
OVERALL MACHINE CONTROL 1 May 1993
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1. DF →Copier
No.Signal Name Definition
1Original Set Originals have been set on the original table
2Copy Start Allowsthe copierto start the copysequence
3Lift Up The DFhas been lifted
4DF Misfeed A misfeed has occurred in the DF
2. Copier →DF
No.Signal Name Definition
1Feed-in Requeststhe DF to feed in the original
2Feed-out Requeststhe DF to feed out the original
3Invert Original Requeststhe DF to invert the original
4Auto Feed Shiftsthe DF to the auto feed mode
5Original Stay The machine attempted to use the DFbut an original from
the previous copy run remainson the exposure glass
31 October1995 OVERALL MACHINE CONTROL
5

5. BASIC OPERATION
1. One-sided Original Feed
When an original is inserted face up into the DF, the Insert Original indicator
light goes out and the DF informs the copier CPU that originals have been set.
When the Start key is pressed, the copier CPU sends the feed-in signal to
the DF. On receipt of this signal, the DF energizes the pick-up solenoid, the
feed-in solenoid, and the belt drive motor in order to feed-in the bottom sheet
of the original stack onto the exposure glass. The pick-up solenoid and the
feed-in solenoid remain energized until the original leading edge reaches the
DF registration sensor. The belt drive motor turns off shortly after the
original’s trailing edge passes the DF registration sensor.
While feeding the original, the DF registration sensor and the paper width
sensor check the original size.
Just when the original trailing edge has passed the DF registration sensor,
the DF CPU sends the copy start signal to the copier.
When the scanner reaches the return position, the copier CPU sends the
feed-out and the feed-in signals to the DF CPU in order to exchange the
original with the next original. At this time, the scanner begins returning to the
home position.
When the scanner comes to the return position after scanning the last
original, the copier CPU only sends the feed-out signal in order to feed-out
the last original.
BASIC OPERATION 1 May 1993
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2. Two-sided Original Feed
Unlike one-sided original feed, the back side of the original must be copied
first to keep the originals and copies in the correct order.
During original feed-in, the sequence is the same as for one-sided feed;
however, the DF CPU also energizes the inverter motor and the inverter
solenoid a short time after the original trailing edge has passed the DF
registration sensor. The belt drive motor continues to feed the original until
the original leading edge passes the feed-out sensor. At this point the inverter
mechanism inverts the original, in preparation for copying the back side.
Then the belt drive motor reverses and the original is fed towards the left
scale and is aligned against the scale. The DF CPU sends the copy start
signal a short time after the original trailing edge has passed the feed-out
sensor.
When the scanner reaches the return position, the copier CPU sends the
invert original signal to the DF CPU in order to make a copy of the front side.
The original is inverted in the same way as for back side copying.
3. Semi-automatic Document Feed
If a single original is inserted into the original table and copied, the DF shifts
to the semi-automatic feed mode and lights the Auto Feed indicator. The
Auto Feed indicator remains on for five seconds after the copier main motor
stops. If another original is inserted within that five-second period, it is
automatically fed and copied.
Document
Feeder
1 May 1993 BASIC OPERATION
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6.POWER DISTRIBUTION
6.1A110/A054 COPIERS
The DF uses threeDC power levels: +24volts,+12 volts, and +5 volts.
When the main switch is turned on, the option transformer receives the wall
outletacpower through the ac driveboard and outputs 10 volts acand26
volts ac totheoptiondcpower supply board.The option dc power supply
board thenconverts the 10volts ac inputto +5 volts dcandthe26 volts ac
input to+24 volts. Then,those twodc voltages are supplied totheDF main
board.
The regulator IC on the DF main boardfurther steps downthe+24 volts to
+12 volts.
115Vac 26Vac
10Vac
220/230/240Vac 5V
+12V+24V
+24V (VA)
+5V (VC)
Regulator
IC
DF Main Board
(PCB1)
AC Drive
Board
(PCB2)
Option
Transformer
(TR2)
Option DC
Power Supply
Board
(PCB6)
POWER DISTRIBUTION1 May1993
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6.2 A111 COPIER
The DF uses three dc power levels: +24 volts, +12 volts, and +5 volts.
When the main switch is turned on, the main transformer receives the wall
outlet ac power through the ac drive board and outputs 10 volts ac and 31
volts ac to the main dc power supply board. The main dc power supply board
then converts the 10 volts ac input to +5 volts dc and the 31 volts ac input to
+24 volts. Then, those two dc voltages are supplied to the DF main board
through the copier main board.
The regulator IC on the DF main board further steps down the 24 volts to +12
volts.
115Vac
220/230/240Vac
AC Drive
Board
(PCB2)
31Vac
10Vac
5V
+12V
+24V
+24V (VA)
+5V (VC)
Regulator
IC
DF Main Board
(PCB1)
Main
Transformer
(TR1)
+24V (VA)
+5V (VC)
Main DC
Power
Supply
Board
(PCB3)
Copier
Main
Board
(PCB1)
Document
Feeder
1 May 1993 POWER DISTRIBUTION
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7. ORIGINAL FEED
7.1 ORIGINAL PICK-UP
After setting the originals on the original table, the originals contact the feeler
[A] of the original set sensor and cause the feeler to move out of the sensor.
The DF then sends the original set signal to the copier CPU to inform it that
the DF will be used. When the Start key is pressed, the pick-up solenoid [B]
is energized. The original stack is then pressed between the pick-up lever [C]
and pick-up roller [D]. The rotation of the pick-up roller advances the bottom
original.
[B]
[C]
[A]
[D]
[A]
ORIGINAL FEED 1 May 1993
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7.2 ORIGINAL SEPARATION
The feed roller [A] and the friction belt [B] are used to feed-in and separate
the originals [C]. Only the bottom original is fed because the friction belt
prevents any other originals from feeding.
Original feed starts when the feed roller starts turning and advances the
bottom original of the stack. The feed roller moves the original past the
friction belt because the driving force of the feed roller is greater than the
resistance of the friction belt. The friction belt prevents multiple feeds
because the resistance of the friction belt is greater than the friction between
original sheets.
[B]
[A]
[B]
[C]
[A]
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1 May 1993 ORIGINAL FEED
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7.3 ORIGINAL FEED-IN MECHANISM
The belt drive motor [A] drives the pick-up roller [B], the feed roller [C], the
pull out roller [D], the relay roller [E], and transport belt [F] via a feed clutch
and a gear train.
The pick-up and feed-in solenoids are energized 100 milliseconds after the
Start key of the copier is pressed. Then 100 milliseconds after the solenoids
are energized, the belt drive motor starts turning. The pulse generator disc
[G] always turns when the belt drive motor is on.
Slightly after the original trailing edge passes the registration sensor, the
relay rollers and the transport belt stop turning.
[F]
[E]
[C]
[D]
[B]
[A]
[G]
ORIGINAL FEED 1 May 1993
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This document feeder has two different ways of stopping originals at the
correct position on the exposure glass. They are called the "thin original
mode" and the "thick original mode". The mode used is determined by the
original select switch [A].
– Original Select Switch –
1. Thin Original Mode
The original is stopped at the correct position on the exposure glass based
on encoder pulse count. The belt drive motor stops shortly after the original
trailing edge passes the DF registration sensor. (Exact timing depends on
registration adjustment.) Thin original mode is selected at the factory.
2. Thick Original Mode
When thick original mode is selected, the belt drive motor remains energized
for an additional 30 encoder pulses as compared to thin original mode. Then,
the belt drive motor pauses and reverses for 21 pulses. This forces the
original against the left scale and thus aligns the edge of the original with the
scale.
After the exposure cycle is completed, the copier sends the feed-out signal to
the DF CPU and the belt drive and feed out motors start turning. At this time,
the copied original feeds out and the next original feeds in.
[A]
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1 May 1993 ORIGINAL FEED
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7.4 ORIGINAL SIZE DETECTION
The DF determines original size (both width and length) through the use of
the original width sensor [A], registration sensor, and pulse generator sensor
[B]. The original’s length is calculated by counting the number of pulses from
the pulse generator while the registration sensor is on.
Original size detection is necessary for the feed-in/feed-out timing of the DF.
[B] [A]
ORIGINAL FEED 1 May 1993
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7.5 ORIGINAL INVERSION MECHANISM
The two sided originals are inverted in the feed-out unit.
1) When the copier Start key is pressed, the two sided original is fed into the
feed-in unit, passing over the DF registration sensor [A]. The feed-out
motor [B] and the inverter solenoid [C] turn on 100 milliseconds after the
original trailing edge passes the registration sensor. When the inverter
solenoid turns on, the inverter pawls [D] rotate counterclockwise.
[D]
[C]
[B]
[E]
[D]
[A]
1)
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1 May 1993 ORIGINAL FEED
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2) The original passes over the exposure glass and feeds into the feed-out
unit.
3) The original is directed onto the exposure glass again by the inverter
pawls. The belt drive motor now reverses 140 milliseconds after the feed
out sensor [E] turns on. The transport belt then moves the original toward
the left scale. Slightly before the original reaches the left scale, the belt
drive motor drops to half speed. This is to prevent damaging the edge of
the original against the left scale.
When the original leading edge reaches the left scale, the belt drive motor
stops. At the same time, the feed-out motor and the inverter solenoid turn
off.
4) After the reverse side of the original is exposed, the belt drive motor, the
feed-out motor, and the inverter solenoid turn on, and the original is fed
into the inverter section. (This is the same as step 2 above.)
5) The original is fed onto the exposure glass again as in step 3 above. The
front side of the original is then copied.
6) After the front side of the original has been exposed, the original is fed
out from the DF.
3) 5)
2) 4)
6)
ORIGINAL FEED 1 May 1993
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7.6 ORIGINAL FEED-OUT MECHANISM
The exit rollers [A] are driven by the inverter motor [B]. When the document
feeder receives the feed out signal from the copier, the transport belt and the
exit rollers start turning simultaneously. The transport belt carries the original
to the inverter rollers [C] and the exit rollers take over the original feed-out.
When the original trailing edge passes the feed-out sensor [D], the feed-out
motor drops to half of its normal speed for 220 milliseconds and then stops.
The lower speed prevents uneven stacking of originals. For A3 or double
letter size originals, the feed-out motor speed does not change due to the
length of the originals.
[A]
[D]
[C]
[B]
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1 May 1993 ORIGINAL FEED
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7.7BELT DRIVE MOTOR CIRCUIT
Adc servomotor is used as the belt drive motor. The driver IC controls the
speed ofthebeltdrive motor.The CPU sends the speeddata (programmed)
to the driver IC. The driver IC sends the pulse-width-modulation (PWM)
signal to the driver circuit,which sends the motor drivepulses.
An encoder in the servomotor has two magnetic sensors thatgeneratetwo
pulsesignals (phase A and B).The driver IC monitors the belt speedand
directionwith these pulse signals and uses the signals to regulatethemotor’s
speed.
Speed
Driver Driver
CN103-1
PWM
ON/OFF
DF Main Board (PCB 1)
Circuit
CPU
IC
Data
Phase A
Phase B
+5V CN103-2
CN103-3
CN103-4
CN102-1
CN102-2
Forward/
Reverse
Encoder
Belt Drive
Motor
ORIGINAL FEED1 May1993
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7.8FEED-OUT MOTOR CIRCUIT
The DF CPU sends thespeed data(highor low) to the driver IC andthe
motor drive circuit. Themotor drive circuitcreates the PWM signal and sends
the motor drive pulses to the feed-out motor.
The frequency generator of the feed-out motor makes avery low voltageac
signal which is fed back to the driver IC. The driver IC monitors the
frequency ofthis ac signal andbased onthefrequency it regulates the
motor speed.
DF Main Board (PCB 1)
CPU
CN104-A2
High/Low
Regulation
FG
Driver Drive
Circuit
IC
ON/OFF
AC Feedback CN104-A15
Voltage CN104-B8
CN104-A12
Motor Feed-out
Motor
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1 May1993 ORIGINAL FEED
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