Ricoh df54 Service Manual

			1 January 1990
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	64 to 105 g/m2 (17 to 28 lb)
Original Feed:	Automatic feed — ADF mode
	Manual feed one by one — SADF mode
Original Table Capacity:	30 sheets / 80 g/m2 (20 lb)
Original Set:	Face up. First sheet on top
Original Transport:	One flat belt
Copy Speed:	12 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 8.8 kg (19.4 lb)

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1 January 1990

2. COMPONENT LAYOUT (NC100)

- Mechanical Components -

2

3

4

5

6

1

	10	9	8	7
1.	Pulse Generator Disk		6.	Inverter Pawl
2.	Friction Belt		7.	Inverter Roller
3.	Pick-up Lever		8.	Transport Belt
4.	Original Table		9.	Pick-up Roller
5.	Exit Roller		10.	Feed Roller
- Electrical Components -			6
		5	7
		4		8
		3		9
		2

	1
	14		10
		13	11
			12
1.	Original Set Sensor	8.	Lift Switch
2.	Registration Sensor	9.	DF Main Board
3.	Pulse Generator Sensor	10.	Feed-out Motor
4.	Original Width Sensor	11.	Inverter Solenoid
5.	Pick-up Solenoid	12.	Feed-out Sensor
6.	Belt Drive Motor	13.	Original Select Switch
7.	Indicator Panel	14.	Feed-in Solenoid

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1 August 1988

2.COMPONENT LAYOUT (FT2260)

-Mechanical Components -

1. Pulse Generator Disk	6.	Inverter Pawl
2. Friction Belt	7. Inverter Roller
3. Pick-up Lever	8.	Transport Belt
4. Original Table	9.	Pick-up Roller
5. Exit Roller	10. Feed Roller

- Electrical

1. Original Set Sensor		9.	DF Power Supply Board
2.	Registration Sensor	10.	Lift Switch
3.	Pulse Generator Sensor	11.	DF Main Board
4. Original Width Sensor		12. Feed-out Motor
5.	Pick-up Solenoid	13.	Inverter Solenoid
6.	Belt Drive Motor	14. Feed-out Sensor
7.	Indicator Panel	15.	Original Select Switch
8.	Interface Board	16.	Feed-in Solenoid

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1 January 1990

3. ELECTRICAL COMPONENT DESCRIPTIONS

Symbol	Name	Function	Location
Motors
M1	Belt Drive Motor	DC servomotor that drives to the transport		6
		belt and feed-in system (pick-up roller, feed
		roller, pull-out roller and relay roller).
M2	Feed-out Motor	DC servomotor that drives the feed-out unit		10
		of the DF.
Solenoids
SOL1	Pick-up Solenoid	Energizes to press the pick-up lever against		5
		the stack of originals in preparation for origi-
		nal feed-in.
SOL2	Feed-in Solenoid	Turns on to engage the feed-in clutch so ro-		14
		tation is transmitted to the feed roller, pull-
		out rollers, and relay rollers.
SOL3	Inverter Solenoid	Energizes to invert the original when copy-		11
		ing two sided originals.
Switches
SW1	Lift Switch	Informs the CPU when the DF is lifted and		8
		also serves as the jam reset switch for the
		DF.
SW2	Original Select	Selects thick original mode or thin original		13
	Switch	mode.
Sensors
S1	Original Set Sen-	Informs copier CPU that originals have		1
	sor	been placed and causes the Insert Original
		indicator to go out.
S2	Registration Sen-	Sets original stop timing and measures origi-		2
	sor	nal length.
S3	Original Width	Determines the width of the originals.		4
	Sensor
S4	Pulse Generator	Generates pulses used to measure the origi-		3
	Sensor	nal length.
S5	Feed-out Sensor	Checks for original misfeeds and sets origi-		12
		nal stop timing when in auto reverse mode.

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1 January 1990

Symbol	Name	Function	Location
Printed Circuit Boards
PCB1	DF Main Board	Controls all DF functions.	9
PCB2	Indicator Panel	Contains operator indicators.	7
	Board

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1 January 1990

4. OVERALL MACHINE CONTROL (NC100)

Copier
Main PCB	DF Main Board

RXD	TXD		Sensors
			Switches
		CPU
TXD	RXD		Solenoids
			Indicators

		Driver	Belt Drive
		IC	Motor
	ROM	Driver	Feed-out
		IC	Motor

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.

7-5

1 August 1988

4. OVERALL MACHINE CONTROL (FT2260)

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.

Also, the DF CPU communicates with the copier using a serial interface. The exchanged signals are shown in the tables on the next page.

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1 June 1990

4. OVERALL MACHINE CONTROL (FT4418)

Copier (PCB1)	Interface (PCB6)	DF Main Board (PCB1)
Main Board	Board

			Sensors
RXD	TXD		Switches
			Solenoids
			Indicators
TXD	RXD	CPU
		Driver	Belt Drive
		IC	Motor
	ROM	Driver	Feed-out
		IC	Motor

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.

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1 January 1990

1. DF → Copier

	No.	Signal Name	Definition
	1	Original Set	Originals are set on the original table
	2	Copy Start	Allows the copier to start copy sequence
	3	Lift Up	The DF is lifted
	4	DF Misfeed	Misfeed occurs in the DF
	2. Copier	→ DF
	No.	Signal Name	Definition
	1	Feed-in	Requests the DF to feed-in the original
	2	Feed-out	Requests the DF to feed-out the original
	3	Invert Original	Requests the DF to invert the original
	4	Auto Feed	Shifts the DF to the auto feed mode
	5	Original Stay	Attempt to use DF but the original from the
			previous copy run remains on the exposure glass

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1 January 1990

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 moves the scanner 100 mm away from the left scale and 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. On receipt of the signal, the copier CPU carries out the original ID measurement while returning the scanner to the home position and starts the copy cycle.

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, but stays 100 mm away from the left scale until the next original is on the exposure glass. At this time the original ID measurement is taken.

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.

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1 January 1990

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.

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1 January 1990

6. POWER DISTRIBUTION (NC100)

					Copier
	DF Main Board		CN808		DC Power
					PCB
		CN101-3	-4	CN302-9	GND
	+5V	CN101-2	-2	-10
					GND
	+12V
		CN101-1	-1	304-8	[5]	~
	Regulator	CN101-4	-3	301-14	[24]
	IC

The DF uses three DC power levels: +24 volts, +12 V, and +5 V.

The AC power from the wall outlet is supplied to the DC power PCB of the copier. The DC power PCB generates two DC voltages: +24V, +5V, and it supplies power to the DF main board.

The regulator IC on the DF main board further steps down the +24V to +12V.

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1 August 1988

6. POWER DISTRIBUTION (FT2260)

The DF uses three dc power levels: +24 volts, +12 volts, and +5 volts.

The line voltage is applied to the DF power supply board where it is stepped down and rectified to +24 volts and +5 volts. Then, those two dc voltages are supplied to the DF main board.

The regulator IC on the DF main board further steps down the +24 volts to +12 volts.

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1 June 1990

6. POWER DISTRIBUTION (FT4418)

							+24V	+12V
	AC Drive Board	115Vac	Optional	26Vac	Optional	+24V (VA)	Regulator
					DC Power
	(PCB2)		Transformer					IC
					Supply Board
			(TR2)
					(PCB5)			5V
		220/240Vac				+5V (VC)
				10Vac
							DF Main Board
							(PCB1)

The DF uses three DC power levels: +24 volts, +12 V, and +5 V.

When the main switch is turned on, the optional transformer receives the wall outlet ac power through the ac drive board and outputs 10 volts ac and 26 volts ac to the optional dc power supply board. The optional dc power supply board then converts the 10 volts ac input to +5 volts dc and the 26 volts ac input to +24 volts. Then, thoes two dc voltsges are supplied to the DF main board.

The regulator IC on the DF main board further steps down the +24V to +12V.

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1 August 1988

7. INTERFACE CIRCUIT (FT2260)

The Copier CPU and the DF CPU communicate via the interface board and fiber optics. The interface board changes the optical signals to electrical signals (only vice versa).

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1 June 1990

7. INTERFACE CIRCUIT (FT4418)

Copier Main Board (PCB1)

Interface Board (PCB6)

DF Main Board (PCB1)

CN133-A14 CN201-A14

	+5V	CN133-B14	CN201-B14	CN206
					RXD
	+5V	CN106-4	CN201-A3	Fiber Optics
	TXD
					CPU
CPU	+5V
		CN106-3	CN201-B3
	RXD			Fiber Optics	TXD
		CN133-A1	CN201-A1	CN106
		CN133-B1	CN201-B1

The copier CPU and the DF CPU communicate via the interface board and fiber optics. The interface board changes the optical signals to electrical signals (and vice versa).

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1 January 1990

7. ORIGINAL FEED

7.1 ORIGINAL PICK-UP

[B]

[C]

[D]

[A]

[A]

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.

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1 January 1990

7.2 ORIGINAL SEPARATION

[B]

[A]

[B]

[C]

[A]

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.

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1 January 1990

7.3 ORIGINAL FEED-IN MECHANISM

[E]

[C]

[D]

[B]

[A]

[F]

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.

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1 January 1990

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].

[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.

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1 January 1990

7.4 ORIGINAL SIZE DETECTION

[B][A]

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.

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