8.5 x 11 8.5 x 14 11x 17

ON OFF b. APS detection timing The APS detection timing differs between the platen mode and DF mode. (1) ADF mode When the RADF mode is selected or an original is set on the RADF original feed tray, APS detection takes place using PS309 (original size/2), PS310 (original size/1), and VR301 (original size). (2) Platen mode When the RADF is closed and PS51 (APS timing) turns ON, L1 (exposure lamp) turns ON and the CCD detects the reflected light to detect the original size in the main scanning direction. Since RADF is still open at this time, the black level of the sky shot (outside the original) and the white level of the original (inside the original) are detected according to whether an original is present. At this time, the original size in the subscanning direction is detected using PS63 to PS65 (APS/1 to APS/3). When the RADF is closed completely and PS311 (ADF open/close) turns ON, CCD reads the white level of the platen cover and the black level in the original. Among the two original sizes detected as discussed above, the larger size is determined as the original size in the main scanning direction.
a. APS detection (1) ADF mode The paper size is detected according to the combination of ON/OFF states of PS309 (original size/2) and PS310 (original size/1) of the RADF's original feed tray and the resistance value of VR301 (original paper size). (2) Platen mode The paper size is detected according to the combination of ON/OFF states of PS63 (APS/1), PS64 (APS/2), and PS65 (APS/3) and the signal read by the CCD sensor. PS63 to PS65 are used to detect the original size in the sub-scanning direction and the CCD sensor is used to detect the original size in the main scanning direction.

Paper exit side

PS65 PS63 PS64

Photo sensor LED

Min. size
a. Input signals (1) APS_TIM (PS51 to SCDB) ADF open/close detection signal [L]: ADF is closed. [H]: ADF is open. (2) APS.1/APS.1_SIG (PS63 to SCDB to ICB) Paper size detection signal [L]: Paper is detected. [H]: Paper is not detected. (3) APS.2/APS.2_SIG (PS64 to SCDB to ICB) Paper size detection signal [L]: Paper is detected. [H]: Paper is not detected. (4) APS3/APS.3_SIG (PS65 to SCDB to ICB) Paper size detection signal [L]: Paper is detected. [H]: Paper is not detected. (5) SIZE_PS_L (PS309 to SCDB to ICB) Paper size detection signal [L]: Paper is detected. [H]: Paper is not detected. (6) SIZE_PS_S (PS310 to SCDB to ICB) Paper size detection signal [L]: Paper is detected. [H]: Paper is not detected. (7) SIZE_ANA (PS301 to SCDB to ICB) Paper size detection signal [L]: Paper is detected. [H]: Paper is not detected. (8) COVER_SIG (SCDB to ICB) Same as APS TIM signal. (9) APS_TIMING (SCDB to PRCB) Same as APS TIM signal. b. Output signals (1) APS_CONT This signal controls ON/OFF states of APS_5V power for driving PS63, PS64, and PS65 (APS1 to APS3). [L]: APS_5V OFF [H]: APS_5V ON

b. PRCB output signals (1) T.CONT (PRCB to HV) This signal turns ON/OFF the voltage applied to the transfer wire. [L]: Transfer voltage ON [H]: Transfer voltage OFF (2) S.CONT (PRCB to HV) This signal turns ON/OFF the voltage applied to the separation wire. [L]: Separation voltage ON [H]: Separation voltage OFF
[5] M14 (Charger Cleaning) Control

CHGM A CHGM B

a. Output signal (1) CHGM_A, B (PRCB to M14) M14 (charger cleaning) drive control signal. The drive direction of M14 is controlled by switching between the drive current directions of two signals. Status Forward stroke of cleaning Backward stroke of cleaning Stop CHGM_A H L L CHGM_B L H L
M14 (charger cleaning) is a DC motor powered by 24 VDC and is controlled by PRCB (printer control board).
a. Purpose of driving M14 (charger cleaning) is used to drive the charging wire cleaning unit. Operation timing The charging wires are cleaned when SW2 (sub power) is turned ON and when the fixing temperature is lower than 50C. They are also cleaned after the specified copy count is reached. * Changeable with the 25-mode DIP SW Cleaning operation Normally, the charging wire cleaning unit is on the front side of the machine. It moves back and forth to clean the charging wires. The movement direction is changed by changing the rotational direction of M14 (charge cleaning). The rotational direction of M14 and the position of the cleaner are detected by monitoring the current value of M14 with PRCB (printer control board).
[6] M10 (Transfer/Separation Cleaning) Control
The rotational direction of M10 and the position of the cleaner are detected by turning on/off the PS52 (transfer/separation PS/F) and PS53 (transfer/separation PS/R). (Di5510/Di7210)
a. Input signals (1) IO_URXD (ADUDB to PRCB) Serial data used to report the ADUDB (ADU drive board) operation state to PRCB (printer control board) (2) REQ1 (ADUDB to PRCB) This signal indicates that sending data from ADUDB (ADU drive board) to PRCB (printer control board) is requested. When ADUDB receives ACK1 and can send data, this signal stands at the [L] level. (3) IO_UCLK (ADUDB to PRCB) Clock signal for IO_URXD signal (4) HP_PS_F (PS52 to ADUDB) Home position detection signal of transfer/separation cleaning member It becomes L when transfer/separation cleaning member reaches the home position. (5) HP_PS_R (PS53 to ADUDB) Reverse position detection signal of transfer/ separation cleaning member It becomes L when transfer/separation cleaning member reaches the reverse position.

24V1 P.GND 5V2 S.GND

MC24V_1 T1FEED_DRV
a. PRCB input signals (1) T1PRE_PS (PS1 to PRCB) Paper passage detection signal (tray 1) [L]: Detected. [H]: Not detected. (2) T2PRE_PS (PS7 to PRCB) Paper passage detection signal (tray 2) [L]: Detected. [H]: Not detected. b. PRCB output signals (1) T1FEED_DRV (PRCB to MC3) MC3 drive control signal (tray 1) [L]: MC3 ON [H]: MC3 OFF (2) T1PREMC_DRV (PRCB to MC4) MC4 drive control signal (tray 1) [L]: MC4 ON [H]: MC4 OFF (3) T2FEED_DRV (PRCB to MC5) MC5 drive control signal (tray 2) [L]: MC5 ON [H]: MC5 OFF (4) T2PREMC_DRV (PRCB to MC6) MC6 drive control signal (tray 2) [L]: MC6 ON [H]: MC6 OFF
[4] Paper Up Drive Control

5V3 TIRM_PS SGND

Tray 1 PS4

T1RISEM_24V T1RISEM_D

5V3 T2UP_PS SGND 5V3 T2RM_PS SGND

PS8 Tray 2 PS10

T2RISEM_24 T2RISEM_D
Paper stacked in the tray is pushed up by transmitting the drive force of M16/17 (tray up drive/ 1/2) to the up/down plate in the tray via drive wires. M16/17 are controlled by the PRCB (printer control board). Related signals are PS2/ 8 (tray upper limit/1/2) and PS4/10 (remaining paper/1/2).
a. Paper up drive control When tray 1/2 is loaded, M16/17 (tray up drive/1/ 2) turns ON to lift the up/down plate in the tray. When PS2/8 (tray upper limit/1/2) detects the upper limit of paper as the paper up/down plate in the tray goes up, it turns ON and consequently M16/17 goes OFF, causing the tray to stop going up. When PS2/8 turns OFF after paper is fed, M16/17 goes ON again to move the paper up/ down plate upward. The up/down plate in the tray is lowered mechanically by its own weight.
b. Paper up drive timing (1) ON timing M16/17 (tray up drive/1/2) is turned ON when loading of a tray is detected. (by shorting wires at both ends of the drawer connector) (2) OFF timing One of M16/17 (tray up drive/1/2) is turned OFF when PS2/8 (tray upper limit/1/2) is turned ON. c. Remaining Paper Detection Control The level of paper remaining in each tray is detected according to the time that M16/17 (tray up drive/1/2) requires to lift up the up/down plate when the tray is set. This lift-up time (operation time of M16/17) is saved in the PRCB (printer control board). After this, the remaining paper is detected using the paper feed counter. The detected remaining paper level is displayed on the operation panel in five steps. PS4/10 (remaining paper/1/2) are used to detect the remaining paper level when it lowers below about 10%.

a. Operation of MC15 (horizontal conveyance MC/L) (1) ON timing for the first paper When the restart of MC3 (feed MC/1) is turned ON. (2) ON timing for the second paper After a specified time when MC1 (registration MC) is turned ON.

2-J-12

a. PRCB input signal (1) HFPS_L (PS5 to PRCB) Paper passage detection signal [L]: Detected. [H]: Not detected (2) HFPS_R (PS6 to PRCB) Paper passage detection signal [L]: Detected. [H]: Not detected b. PRCB output signal (1) HFMC_L (PRCB to MC15) MC15 drive control signal [L]: MC15 ON [H]: MC15 OFF (2) HFMC_R (PRCB to MC16) MC16 drive control signal [L]: MC16 ON [H]: MC16 OFF

2-J-13

[5] Paper Up Drive Control
5V3 TIUP_PS SGND 5V3 TIRM_PS SGND

PS2 Tray 1 PS4

7272ma2009

2-J-14

a. PRCB input signals (1) T1UP_PS (PS2 to PRCB) Paper upper limit detection signal (tray 1) [L]: Not detected. [H]: Detected. (2) T1RM_PS (PS4 to PRCB) Remaining paper detection signal (tray 1) [L]: Not detected. [H]: Detected. (3) T1UP_PS (PS8 to PRCB) Paper upper limit detection signal (tray 2) [L]: Not detected. [H]: Detected. (4) T1RM_PS (PS10 to PRCB) Remaining paper detection signal (tray 2) [L]: Not detected. [H]: Detected. b. PRCB output signals (1) T1RISEM_24V (PRCB to M16) M16 ON/OFF control signal (tray 1) (2) T2RISEM_24 (PRCB to M17) M17 ON/OFF control signal (tray 2)

7272ma2010

No paper in the tray is detected by PS3 (no paper /1) and PS9 (no paper /2), and which is controlled by the PRCB (printer control board).
a. PRCB input signals (1) T1_0PS (PS3 to PRCB) No paper detection signal (tray 1) [L]: Paper does not exist in tray. [H]: Paper exists in tray. (2) T2_0PS (PS9 to PRCB) No paper detection signal (tray 2) [L]: Paper does not exist in tray. [H]:Paper exists in tray.

2-J-15

TRAY 3 PAPER FEED UNIT (Di551/Di650)
Drive pulley (for wire C/D) Tray up drive motor/3 (M18) Feed roller
Double feed prevention roller Side guide Side guide Drive pulley (for wire A/B)
End stopper Paper size VR/3 (VR3) Paper size PS/1-3 (PS17)

Paper size PS/2-3 (PS18)

Paper lift-up a) Hoisting of up/down plate Paper feed tray is driven by wires. When the paper tray is loaded, the tray up drive motor 3 (M18) rotates to wind the wires around the drive pulleys and consequently the up/down plate in the tray moves up. When the tray upper limit PS/3 (PS14) detects the actuator of the roller that has been moved up by paper, the tray up drive motor 3 (M18) stops.
Paper size detec- Width: VR tion *2 Length: Photosensor (Universal) + Actuators (two) 1st paper feed Photosensor + Actuator paper loop mech- + Magnetic clutch anism*3

Paper feed roller

First paper feed paper loop mechanism When paper feed starts, paper is fed to the preregistration roller by the feed roller and paper feed rollers. The fed out paper operates the actuator of the paper feed PS/3 (PS13), turning it ON. The feed and paper feed rollers remain ON for a specified time after the actuation of the paper feed PS/3 (PS13) causing a paper loop to form against the pre-registration rollers which are not turning. In this way paper skew is corrected.

a. Paper up drive control When tray 3 is loaded, M18 (tray up drive/3) turns ON to lift the up/down plate in the tray. When PS14 (tray upper limit/3) detects the upper limit of paper as the paper up/down plate in the tray goes up, it turns ON and consequently M18 goes OFF, causing the tray to stop going up. When PS14 turns OFF after paper is fed, M18 goes ON again to move the paper up/down plate upward. The up/down plate in the tray is lowered mechanically by its own weight.
b. Paper up drive timing (1) ON timing M18 (tray up drive /3) is turned ON when loading of a tray is detected. (by shorting wires at both ends of the drawer connector) (2) OFF timing M18 (tray up drive/3) is turned OFF when PS14 (tray upper limit/3) is turned ON. c. Remaining Paper Detection Control The level of paper remaining in the tray is detected according to the time that M18 (tray up drive/3) requires to lift up the up/down plate when the tray is set. This lift-up time (operation time of M18) is saved in the PRCB (printer control board). After this, the remaining paper is detected using the paper feed counter. The detected remaining paper level is displayed on the operation panel in five steps. PS16 (remaining paper/3) is used to detect the remaining paper level when it lowers below about 10%.
a. PRCB input signals (1) T3UP_PS (PS14 to PRCB) Paper upper limit detection signal [L]: Not detected. [H]: Detected. (2) T3RM_PS (PS16 to PRCB) Remaining paper detection signal [L]: Not detected. [H]: Detected. b. PRCB output signals (1) T3RISEM_24 (PRCB to M18) M18 ON/OFF control signal
5V3 T3SIZE_S_PS SGND 5V3 T3SIZE_L_PS SGND 3.3V2 T3SIZE_VR AGND

PS17 PS18 VR3

The paper size in tray 3 is detected using PS17 (paper size/1-3), PS18 (paper size/2-3), and VR3 (paper size/3). Based on the detection signals, the PRCB (printer control board) judges the paper size.
The length of paper is detected using PS17/18 (paper size/1-3/2-3). Variable resistor (VR3) interlocked with the guide position is installed at the bottom of the tray to detect the width of paper. The relationships between the sensors and paper sizes (lengths) are as follows: Paper size Sensor PS17 PS18 8.5 x 11 or less OFF OFF A4R to B5R ON OFF F4 or larger ON ON
a. PRCB input signals (1) T3SIZE_S_PS (PS17 to PRCB) Paper size detection signal [L]: Paper does not exist. [H]: Paper exists. (2) T3SIZE_L_PS (PS18 to PRCB) Paper size detection signal [L]: Paper does not exist. [H]: Paper exists. (3) T3SIZE_VR (VR3 to PRCB) Paper width detection signal

5V3 T3_0PS SGND

No paper in the tray is detected by PS15 (no paper/3), and which is controlled by the PRCB (printer control board).
When the tray becomes empty, PS15 (no paper/ 3) is turned OFF, displaying a message on the LCD via OB1 (operation board/1).
a. PRCB input signals (1) PS15 (PS15 to PRCB) No paper detection signal [L]: Paper does not exist in tray. [H]: Paper exists in tray.

[4] Paper Up/Down Control

5V3 BPDN_PS SGND

DCPS PRCB
Paper in the by-pass tray is pushed up/down by M20 (up/down motor/BP). M20 is controlled by PRCB (printer control board). Related signals are PS34 (tray upper limit /BP) and PS35 (tray lower limit /BP).
a. Paper up/down control M20 (up/down motor/BP) is turned ON to push up paper. When PS34 (tray upper limit/BP) detects the paper upper limit and turns ON, M20 turns OFF to stop pushing up paper. When paper is fed and consequently PS34 turns OFF, M20 turns ON again, maintaining the upper limit position of paper. Paper up timing ON timing At start of copying OFF timing M20 (up/down motor/BP) is turned OFF when PS34 (tray upper limit /BP) is turned ON. Paper down timing ON timing When there is no paper or a paper jam occurs. OFF timing M20 (up/down motor/BP) is turned OFF when PS35 (tray lower limit/BP) is turned ON.

b. (1) (2)

c. (1) (2)

5V3 BPUP_PS SGND

BPUDM_A BPUDM_B
a. PRCB input signals (1) BPUP_PS (PS34 to PRCB) Paper upper limit position detection signal (bypass tray) [L]: Not detected. [H]: Detected. (2) BPDN_PS (PS35 to PRCB) Paper lower limit position detection signal (bypass tray) [L]: Not detected. [H]: Detected. b. PRCB output signal (1) BPUDM_A, B (PRCB to M20) M20 drive control signal
5V2 S.GND 5V3 BPSIZE_S_PS SGND 5V3 BPSIZE_L_PS SGND 5VA BPSIZE_VR

PS31 PS32 VR5

The size of paper in the by-pass tray is detected by PS31 (paper size/1-BP), PS32 (paper size/2BP), and VR5 (paper size/BP). Based on the detection signals, PRCB (printer control board) judges the paper size.
The length of paper is detected by PS31 (paper size/1-BP) and PS32 (paper size/2-BP). The bypass tray is provided with a variable resistor (VR5) interlocked with the guide position to judge the paper width according to the change in the resistance value. The relationships between the sensors and paper sizes (lengths) are as follows: Paper size 8.5 x 11 Sensor or less PS31 PS32 OFF OFF A4R to B5R ON OFF F4 or larger ON ON
a. PRCB input signals (1) BPSIZE_S_PS (PS31 to PRCB) Paper size detection signal [L]: Paper does not exist. [H]: Paper exists. (2) BPSIZE_L_PS (PS32 to PRCB) Paper size detection signal [L]: Paper does not exist. [H]: Paper exists. (3) BPSIZE_VR (VR5 to PRCB) Paper width detection signal
5V2 S.GND 5V3 BP_OPS SGND

Others

ADU pre-registration mechanism In the ADU, paper is looped by the ADU pre-registration roller to correct paper inclination in the conveyance section. The ADU pre-registration roller stops when the loop roller motor (M6) stops; however, the ADU conveyance roller continues to feed paper at a constant speed, forming a paper loop between the ADU pre-registration roller and ADU conveyance roller. As a result, paper inclination is corrected. When M6 starts, the ADU pre-registration roller starts rotating to feed the paper to the second feed section. An ADU conveyance MC (MC13) is provided to turn ON/OFF the drive force of ADU conveyance rollers 1 and 2 in order to stop the looped paper temporarily and to adjust the loop size. In addition, an ADU deceleration MC (MC2) is provided to turn ON/OFF the drive force of ADU conveyance 2-N-6
[3] Loop/Second Paper Feed Control
24V 24V A /A B /B 5V3 LOOP PS S.GND +5V PGND START/STOP CLK CW/CCW LD H/L PGND +24V MC24V 2ND MC 5V2 EDGE PS S.GND 5V2 2ND PS S.GND

MC1 PS43 PS44 PS50

5V2 ADUEXT PS S.GND 5V2 24V1 S.GND 24V1 5V2 S.GND P.GND -5V1 DEF VIDEO GMD 5V2 -5V GND DEF SI DEF CLK DEF LED 24V1
The paper fed from each tray is fed to the second paper feed section. The second paper feed takes place as the result of the transmission of the drive force from M5 (conveyance) to the second paper feed roller via MC1 (registration). The second paper feed section is preceded by a loop roller used to form a paper loop, and this conveyance section is also used for the paper fed from the LCT. It is not used for the paper fed from the bypass tray or ADU. The loop roller is driven by M6 (loop roller). The above parts are controlled by PRCB (printer control board) via ADUDB (ADU drive board). M6 is driven by PRCB directly. Related signals are PS36 (loop), PS43 (leading edge), PS44 (registration), and PS50 (ADU preregistration).
a. Loop control After a lapse of the specified time from turning ON of PS44 (registration) by the paper fed from each tray or the ADU at a high speed, M6 (loop roller) is turned OFF to form a paper loop in the registration section. Second paper feed control After formation of a paper loop under loop control, MC1 (registration) is turned ON to transmit the drive force of M5 (conveyance) to the second paper feed roller, starting the second paper feed. Image position correction control Mis-centering of the paper fed from each tray is detected by PS70 (paper mis-centering) and the paper leading edge timing is detected by PS43 (leading edge) and they are corrected at the time of image write.

a. Input signals (1) FIXEXIT_PS (PS30 to PRCB) Detection signal of paper passage at fixing unit exit [L]: Detected. [H]: Not detected. (2) DECUR_PS (PS42 to ADUDB) Reverse/exit gate open/close detection signal [L]: Gate is open. [H]: Gate is closed. (3) ADU_REV (PS45 to ADUDB) ADU reverse section paper passage detection signal [L]: Detected. [H]: Not detected. (4) REV_PS (PS46 to ADUDB) ADU gate open/close detection signal [L]: Gate is open. [H]: Gate is closed. b. Output signals (1) GATE_DR (ADUDB to SD7) SD7 (reverse gate) ON/OFF drive signal [L]: SD7 ON [H]: SD7 OFF (2) A, /A (PRCB to M7) M7 (paper exit) A-phase drive control pulse signal (3) B, /B (PRCB to M7) M7 (paper exit) B-phase drive control pulse signal (4) A, /A (ADUDB to M8) M8 (reverse/exit) A-phase drive control pulse signal (5) B, /B (ADUDB to M8) M8 (reverse/exit) B-phase drive control pulse signal

2-N-12

[6] ADU Paper Conveyance/Feed Control

24V 24V A /A B /B

+5V PGND START/STOP CLK CW/CCW LD H/L PGND +24V 5V2 ADU JAM S.GND 5V2 ADU REV S.GND 5V2 REV PS S.GND 5V2 HD PS S.GND 5V2 ADUCR PS S.GND 5V2 ADUDN PS S.GND 5V2 ADUEXIT PS S.GND MC24V LOCK SD 5V2 24V1 S.GND MC24V ADUDN MC

PS41 PS45

SD9 MC2 MC13

MC24V ADUCR MC

The paper fed from the ADU paper reversal section is fed by transmitting the drive force of M5 (conveyance) to ADU conveyance rollers 1 to 4. Paper is then fed to the second paper feed section by the drive force of M6 (loop roller). In the ADU conveyance section, pre-loop control is performed to correct paper skew forcibly. To perform this control, MC2 (ADU deceleration) and MC13 (ADU conveyance) are provided. Related signals 2-N-13
are PS41 (ADU conveyance/1), PS45 (ADU paper reverse), PS46 (reverse/exit), PS48 (ADU paper conveyance/2), PS49 (ADU deceleration), and PS50 (ADU pre-registration). SD9 (ADU lock) is provided to lock the handle of the ADU.
a. ADU conveyance control The paper fed from the ADU paper reversal section is fed to ADU pre-registration rollers at a high speed by transmitting the drive force of M5 (conveyance) to ADU conveyance rollers 1 to 4. ADU conveyance rollers 1 and 2 are turned ON/OFF by MC13 (ADU conveyance) and ADU conveyance rollers 3 and 4 are controlled by MC2 (ADU deceleration). After a lapse of the specified time from turning ON of PS49 (ADU deceleration), MC2 and MC13 are turned OFF to press the paper against the ADU pre-registration roller, forming a paper loop. MC13 is turned ON/OFF only when the paper length is 325 mm or longer. If the paper length is less than 325 mm, it stays ON during copying. ADU feed control M6 (loop roller) starts rotating at a high speed after a lapse of the specified time from detection of the leading edge of paper by PS50 (ADU preregistration). Thus, the ADU pre-registration roller starts rotating to feed paper to the second paper feed section. At this time, MC2 (ADU deceleration) and MC13 (ADU conveyance) are turned OFF so that the drive force of M5 (conveyance) which is also used to drive the second paper feed section is not transmitted to ADU conveyance rollers 1, 2, 3, and 4. MC2 and MC13 are turned ON after a lapse of the specified time from detection of the trailing edge of paper by PS49 (ADU deceleration), proceeding to feed the next sheet of paper. After a lapse of the specified time from detection of the leading edge of paper by PS44 (registration), M6 starts rotating at a low speed. MC1 (registration) is turned ON after formation of a paper loop by the registration roller, thus writing the image on the back side. ADU lock control The ADU handle is locked by SD9 (ADU lock). PS47 (ADU handle) detects the handle position to determine whether the handle is locked or released.

This machine counts copies using a software counter. (1) Paper exit counter The count increases by 1 each time PS37 (paper exit) which has been ON is turned OFF (two counts in the dual-sided document copy mode). <Operation of each counter> a. Copy quantity display counter on OB Displays the count of ejected papers b. C (K) This counter counts in sync with the paper exit counter. c. C (T) This counter counts in sync with the paper exit counter.

[6] Option Control

FNS (FN-112/FN-6/FN-121/ FN-10/FN-113/FN-122)

SF (OT-104)

LCT (C-403/C-404)
CV (COPY VENDOR) PRCB DCPS
24V1 P.GND 5V2 S.GND 12V1 7272ma2021
Options such as LCT and FNS are controlled by the PRCB (printer control board).
FNS incorporates CB which exchanges only control data with PRCB (printer control board) of the main body. LCT, FNS, and HDD are powered by the DCPS (DC power supply unit).

2-P-10

<Functions and output timings of signals for copy vendors> Connector Pin No. Signal name Description Output timing DV24V Key counter power supply Always C(K) SIG C(K) GND C(K) DRIVE P. GND Key counter connection recognition Signal ground Key counter signal count up 100-ms L-signal output after paper ejection Power ground Signal type 24 V, 300 mA 2 UNIT EXPLANATION
Vendor Copy Copying signal 1
Output from the moment Open collector START PRINT button is 5V, 200 mA pressed to the moment paper ejection is completed. Common to main body tray. 100-ms L-signal output in sync with paper feed. Output when paper size is changed.
Vendor FEED Paper feed signal 2
Paper size 0 Paper size signal Paper size 1 Paper size 2 Paper size 3 Vendor screen CPF SIG0 CPF SIG1 P. GND Power ground Double-sided copy selection signal
Output when ADU mode is selected.
CPF mode selection signal Output when copy or printer mode is selected.

2-P-11

DISASSEMBLY/ASSEMBLY
This section explains how to disassemble and reassemble the machine. When disassembling and reassembling the machine, follow the precautions given below. 1. Be sure the power cord has been unplugged from the wall outlet. 2. The disassembled parts must be reassembled following the disassembly procedure in reverse unless otherwise specified. 3. Care should be taken not to lose small parts. Care should also be taken not to install small parts in wrong places. 4. Do not operate the machine before installing all the disassembled parts completely. 5. Removal of some screws is prohibited in this section. Never loosen them.

Metal bead

3Four turns

Front Five turns

Five turns Metal bead Wire stopper
Pulley 1 Exposure unit mounting piece V-mirror pulley Wire stopper V-mirror unit Exposure unit mounting piece Drive pulley Wire stopper Spring Pulley 2 Pulley 1

Pulley 3

5 Spring fixing plate 7

Drive pulley

6 Spring fixing plate

Pulley 3 Pulley 2

V-mirror pulley

Wire stopper

Caution: There are two grooves in the wire stopper. Ensure that the outer groove is at the rear and the inner groove is at the front. (5) Reverse the inner wire at pulley 2, pass it along the inside of the V-mirror pulley and pulley 3, then attach the wire terminal to the spring fixing plate. At this time, secure the spring fixing plate temporarily with one screw.
(6) Install the other wire following the same procedure. (7) Loosen each screw that was tightened temporarily, install the spring on the spring fixing plate, and tighten each screw.
[6] Cleaning the Slit Glass and Platen Glass
Caution: Be sure the power cord has been unplugged from the wall outlet. (1) Remove the original stopper plates (left and rear), platen glass, and top cover (right, left, front center, and rear center). (See "EXTERNAL SECTION.") (2) Remove two screws to detach the slit glass. (3) Place the removed slit glass and platen glass on a rag and clean with isopropyl alcohol and waste.
[7] Replacing the Scanner Motor (M11)
Caution: Be sure the power cord has been unplugged from the wall outlet. a. Procedure (1) Remove the RADF unit, original stopper plates (left and rear), platen glass, and top cover (right, left, front center, and rear center). (See "EXTERNAL SECTION.") (2) Remove one connector (CN639) from the APS timing PS (PS51).

Connector(CN639)

Slit glass

Slit glass Screw

(3) Remove the hinge mounting plate (rear side) from the scanner unit. (12 screws) (4) Remove four screws from the scanner motor (M11), then remove the scanner belt and the scanner motor.
(5) Install the scanner motor (M11) and the scanner belt. Tighten the scanner motor loosely with four screws. Caution1: Make sure to install the belt in the middle of two pulleys. Also make sure that the belt is not placed on the edges of pulleys, or that it is running off from the pulleys. Caution2: Tighten the motor by first tightening the screw and then give it one turn to loosen slightly.

Scanner Belt

(7) Pull the spring scale upward, and tighten the scanner motor (M11) tightly with the tension pressure of 2 0.2kgf. (Use four screws) Caution: Make sure that the scanner motor moves up and down when confirming the tension pressure.
Spring scale Scanner motor (M11)

(3) Reinstall the above parts following the removal steps in reverse.
[1] Removing and Reinstalling the Drum Unit
Caution: Be sure the power cord has been unplugged from the wall outlet. Caution1: Be sure to put a drum cover over the removed drum unit and store the drum unit in a dark place. Caution2: When installing or removing the drum unit, do not rotate it in the direction opposite to the specified one. Rotating the drum unit in the opposite direction during copy operation could damage the cleaning blade. Caution3: When installing or removing the drum unit, take care not to touch the separation claw. Caution4: When installing a new drum, be sure to enter mode 25 and select "Copy Count by Parts to be Replaced" to reset OPC drum counter. a. Procedure (1) Open the left and right front doors. (2) While pressing the solenoid release lever on top of the ADU rack to the left, flip the ADU rack pullout lever to the left. (3) Loosen three screws to remove the drum cover.

Drum cover Screws

(5) Loosen the screw of the blade fixing component.

Blade fixing component

Release
(6) Remove the two screws securing the drum unit. (7) Release the toner supply pipe in the direction of the arrow. (8) Remove the screw securing the coupling to detach the drum shaft coupling and drum coupling. (9) Hold the two sections shown in the figure and pull out the drum unit.
Screws Toner supply pipe Drum unit
ADU rack pullout lever Solenoid release lever

Hold here

Drum coupling
Screw Drum shaft coupling
(4) Loosen one screw and slide the blade fixing component in the direction of the arrow until it stops to release the crimp of the cleaning blade.
(10) Reinstall the above parts following the removal steps in reverse. Caution: To install the coupling, see "[2] Installing the Coupling."
[2] Installing the Coupling
Caution: Be sure the power cord has been unplugged from the wall outlet. a. Procedure (1) Clean the outer surface of the drum coupling and drum shaft coupling with isopropyl alcohol and waste. (2) Insert the drum coupling aligning the protrusions on the drum coupling with the notches in the drum.
(4) Turn the head of the drum coupling clockwise so that the flange section on the drum shaft coupling is flush.
Drum coupling Flange section Drum notches

Drum shaft coupling

(5) Tighten with screw.
Drum coupling Protrusions
(3) Insert the drum shaft coupling so that the D cut section of the drum shaft coupling matches the drum shaft.

Drum shaft D cut section

[3] Removing, Cleaning, and Reinstalling the Drum
Caution: Be sure the power cord has been unplugged from the wall outlet. Caution1: Be careful not to touch the drum or the cleaning blade with bare hands, or damage them. Caution2: When leaving the drum, be sure to put the drum cover over the drum and store it in a dark place. Caution3: When reinstalling the drum, cleaning blade, and toner guide roller, apply setting powder to the entire surface of the drum and also to the cleaning blade regardless of whether the parts are new or old. Caution4: After applying setting powder to the drum, perform the following before installing the drum unit in the main body. 1) With the charging corona unit and developing unit removed, turn the drum once (to prevent setting powder from scattering onto the charging corona unit, and to prevent image defects). 2) When installing a new drum, be sure to enter mode 25 and select "Copy Count by Parts to be Replaced" to reset drum counter. (See "ADJUSTMENT.")

(6) Reinstall the above parts following the removal steps in reverse. Caution1: When reinstalling the rollers, pay attention to their orientation. Caution2: Check that no grease or the like remains on each roller. 3-K-2
a. (1) (2) (3) Procedure Remove the paper feed unit. Remove two connectors (CN850, 851). Remove two stop rings to detach the pre-registration MC/3 (MC8) and feed MC/3 (MC7).
Caution1: After replacing or reinstalling the wires, manually rotate the up/down drive shaft to check that the tray moves up and down smoothly. Caution2: Be sure to install the wires so that they do not cross or ride over each other. <Removing Wires> (1) Remove the paper feed unit. (2) Remove two claws to remove the tray front cover. (3) Remove two screws to remover shaft supporting plate. (4) Remove three screws to remove the wire cover(front) and wire cover (rear).
Screws Wire cover (rear) Screws Wire cover (front) Shaft supporting plate

Tray cover (front)

(5) Remove the front and rear wires according to steps 1 to 7 below.
Remove the E-ring to detach the wire restraining cover and pulley.
Remove two E-rings to slide out the drive pulley. Wire D (white) E-ring E-ring Wire D (white) Wire C (black) Wire C (black)

Wire restraining cover

Pulley E-ring Drive pulley
and three E-rings and pull out the drive pulley. Wire B (white) Wire A (black) E-ring Wire A (black) E-ring
298.91 mm (Tray 3) Wire A, C 589.21 mm (Tray 3) Wire B, D
inside the drive shaft hole, push in the drive pulley, and secure with E-rings. Wire D (white) Wire C (black) E-ring E-ring

3. Pass wire C through

the up/down plate.
inside the drive shaft hole, push in the drive pulley, and secure with E-rings. Next, install the drive pulley holder. Wire C (black) Wire B (white) Wire D (white) Wire A (black)

E-ring E-ring

PAPER FEED UNITS OF TRAYS 3 AND 4 (Di5510/Di7210)
Caution: Trays 3 and 4 have the same shape and mechanism.
[2] Removing and Reinstalling the Paper Feed Tray 3 and 4
Warning: When removing the tray, stand in a proper position so that you do not hurt your back and waist. If the tray contains paper, remove all paper before removing the tray. Caution: Be sure the power cord has been unplugged from the wall outlet. a. Procedure (1) Draw out paper feed tray 3. (2) Remove the paper feed unit. (3) Remove eight screws and detach the tray 3 by lifting.

3-N-12

[11] Removing and Reinstalling the ADU Stand
Warning: The interlock which is turned OFF when the front right or left door opens or closes should never be turned ON forcibly with the ADU stand drawn out. Warning: Removal and reinstallation of the ADU stand involve carrying a heavy load so it should be performed by two persons. Caution: Be sure the power cord has been unplugged from the wall outlet. Procedure Draw out the ADU stand from the main body. Remove the fixing unit. (See "FIXING UNIT.") Remove the transfer/separation corona unit. (See "CORONA UNIT.") Remove the second paper feed unit. Remove the front right door and the front left door. (See "EXTERNAL SECTION.")
(8) Disconnect the three relay connectors (CN445, 446, 447). Caution: Disconnect each connector on the ADU stand.
Screw Connector cover Stay Screw

Relay connector (CN446)

Relay connector (CN447)

Relay connector (CN445)

(6) Remove one screw (in the case of the Di551/ Di650) or loosen one screw (in the case of the Di5510/Di7210) to detach the connector cover. (7) Remove the screw to loosen the stay.

3-N-13

(9) Remove one screw to release the lock of the handle(right). (10) Remove the two screws securing the guide rails on the paper feed side and paper exit side. Caution: Do not mistake the screws securing the guide rails for screws(black) that must not be removed. (Black screws must not be removed) (11) To remove the ADU stand, one person holds the handle(right) on the paper-feed side, and the other holds the the handle(left) on the fixing unit. Then, they lift up the ADU stand.
Screws Handle (left) Handle (right)
[12] Removing and Reinstalling the Preregistration Roller
Warning: The interlock which is turned OFF when the front right or left door opens or closes should never be turned ON forcibly with the ADU stand drawn out. Warning: Removal and reinstallation of the ADU stand involve carrying a heavy load so it should be performed by two persons. Caution: Be sure the power cord has been unplugged from the wall outlet. a. Procedure (1) Remove the front and rear registration springs. Caution: When reinstalling, pay attention to the location of the registration spring hook. Remove the E-ring (6) Press the cleaner coupling and pull out the pin. Remove the spring. Remove the front and rear E-rings (8) and remove each bearing.

SAFETY.FM Page 1 Friday, November 1, 2002 1:54 PM
SAFETY AND IMPORTANT WARNING ITEMS
Read carefully the Safety and Important Warning Items described below to understand them before doing service work.

IMPORTANT NOTICE

Because of possible hazards to an inexperienced person servicing this copier as well as the risk of damage to the copier, Minolta Corporation strongly recommends that all servicing be performed only by Minolta-trained service technicians. Changes may have been made to this copier to improve its performance after this Service Manual was printed. Accordingly, Minolta Corporation does not warrant, either explicitly or implicitly, that the information contained in this Service Manual is complete and accurate. The user of this Service Manual must assume all risks of personal injury and/or damage to the copier while servicing the copier for which this Service Manual is intended. Therefore, this Service Manual must be carefully read before doing service work both in the course of technical training and even after that, for performing maintenance and control of the copier properly. Keep this Service Manual also for future service.
In this Service Manual, each of three expressions " DANGER," " WARNING," and " CAUTION" is defined as follows together with a symbol mark to be used in a limited meaning. When servicing the copier, the relevant works (disassembling, reassembling, adjustment, repair, maintenance, etc.) need to be conducted with utmost care.
DANGER :Action having a high possibility of suffering death or serious injury WARNING :Action having a possibility of suffering death or serious injury CAUTION :Action having a possibility of suffering a slight wound, medium trouble, and property

damage

Symbols used for important warning items are defined as follows:
:Precaution :Prohibition :Direction

General precaution

Electric shock

Heated surface

General prohibition
Do not touch with wet hand

Do not disassemble

General instruction

Unplug

Ground/Earth
SAFETY.FM Page 2 Friday, November 1, 2002 1:54 PM

SAFETY WARNINGS

[1] MODIFICATIONS NOT AUTHORIZED BY MINOLTA
Minolta copiers are renowned for their high reliability. This reliability is achieved through high-quality design and a solid service network. Copier design is a highly complicated and delicate process where numerous mechanical, physical, and electrical aspects have to be taken into consideration, with the aim of arriving at proper tolerances and safety factors. For this reason, unauthorized modifications involve a high risk of degradation in performance and safety. Such modifications are therefore strictly prohibited. the points listed below are not exhaustive, but they illustrate the reasoning behind this policy.

SAFETY.FM Page 4 Friday, November 1, 2002 1:54 PM
Do not bundle or tie the power cord. Overheating may occur there, leading to a risk of fire.
Check whether dust is collected around the power plug and wall outlet. Using the power plug and wall outlet without removing dust may result in fire. Do not insert the power plug into the wall outlet with a wet hand. The risk of electric shock exists.
When unplugging the power cord, grasp the plug, not the cable. The cable may be broken, leading to a risk of fire and electric shock.

WARNING: Wiring

Never use multi-plug adapters to plug multiple power cords in the same outlet. If used, the risk of fire exists. When an extension cord is required, use a specified one. Current that can flow in the extension cord is limited, so using a too long extension cord may result in fire. Do not use an extension cable reel with the cable taken up. Fire may result.

WARNING: Ground Lead

Check whether the copier is grounded properly. If current leakage occurs in an ungrounded copier, you may suffer electric shock while operating the copier. Connect the ground lead to one of the following points: a. Ground terminal of wall outlet b. Ground terminal for which Class D work has been done
SAFETY.FM Page 5 Friday, November 1, 2002 1:54 PM
Pay attention to the point to which the ground lead is connected. Connecting the ground lead to an improper point such as the points listed below results in a risk of explosion and electric shock: a. Gas pipe (A risk of explosion or fire exists.) b. Lightning rod (A risk of electric shock or fire exists.) c. Telephone line ground (A risk of electric shock or fire exists in the case of lightning.) d. Water pipe or faucet (It may include a plastic portion.) 2.Installation Requirements
WARNING: Prohibited Installation Place
Do not place the copier near flammable materials such as curtains or volatile materials that may catch fire. A risk of fire exists. Do not place the copier in a place exposed to water such as rain water. A risk of fire and electric shock exists.
WARNING: Nonoperational Handling
When the copier is not used over an extended period of time (holidays, etc.), switch it off and unplug the power cord. Dust collected around the power plug and outlet may cause fire.

Transfer/separation cleaning motor (M10)
CHAPTER1.FM Page 11 Friday, November 1, 2002 2:02 PM
[7] ADU Conveyance Drive Section
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Pre-transfer roller Registration roller Registration MC (MC1) Registration roller knob ADU conveyance roller/4 Conveyance motor (M5) ADU deceleration MC (MC2) ADU conveyance MC (MC13) ADU gate Reverse/exit roller knob 11. 12. 13. 14. 15. 16. 17. 18. 19. FRONT Reverse/exit roller Reverse/exit motor (M8) Reverse/exit gate ADU reverse motor (M9) ADU reverse roller ADU conveyance roller/1 ADU conveyance roller/2 ADU conveyance roller/3 Conveyance belt
CHAPTER1.FM Page 12 Friday, November 1, 2002 2:02 PM
[8] Paper Exit Drive Section

Paper exit motor (M7)

Paper exit roller

Exit conveyance roller

[9] Toner Supply Drive Section

Rear View

Front View 1. 2. 3. Toner cartridge Toner supply screws Toner bottle motor (M13) 4. 5. 6. Toner supply screw Toner supply motor (M12) Toner conveyance screw
CHAPTER1.FM Page 13 Friday, November 1, 2002 2:02 PM
[10] Optics Drive Section
Scanner motor (M11) Scanner drive wire (rear) Exposure unit

1. 2. 3.

Scanner drive wire (front) V-mirror unit
CHAPTER1.FM Page 14 Friday, November 1, 2002 2:02 PM
chapter2_Cover.fm Page -1 Friday, November 1, 2002 2:06 PM

UNIT EXPLANATION

2 UNIT EXPLANATION
chapter2_Cover.fm Page 0 Friday, November 1, 2002 2:06 PM
chapter2_A.fm Page 1 Friday, November 1, 2002 2:04 PM

EXTERNAL SECTION

[1] Composition
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. Sub power switch (SW2) Operation panel RADF Right side cover (upper) Developing suction filter cover Bypass tray Right side cover (lower rear) Vertical conveyance door Right side cover (lower middle) Right side cover (lower front) Tray 3
12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. Tray 2 Tray 1 Front left door Front right door Toner access door Main power switch (SW1) Paper exit tray Left side cover Rear cover Optional cover Ozone filter cover
chapter2_A.fm Page 2 Friday, November 1, 2002 2:04 PM
chapter2_B.fm Page 1 Friday, November 1, 2002 2:05 PM

DRIVE SECTION

Scanner motor (M11) Drum motor (M2) Toner bottle motor (M13) 2 UNIT EXPLANATION
Developing motor (M3) Fixing motor (M4)

Loop roller motor (M6)

Paper feed motor (M1)

[2] Mechanisms

Mechanism Drum drive*1 Driven Parts Method Drum, Toner guide Gear drive (dediroller, Toner con- cated motor) veyance screw, and Separation claw swing

5V2 S.GND 24V1 5V2 S.GND P.GND
(2) When PS61 (scanner HP) is ON

DCPS SCDB

PS61 M11 (scanner) is driven by SCDB (scanner drive board) and is controlled by PRCB (printer control board). The related signal is PS61 (scanner HP).

Platen APS read position

a. Operation of M11 (scanner) M11 (scanner) is a 3-phase stepping motor driven by the 3-phase bipolar constant-current drive method. The motor is turned ON/OFF by supplying/stopping clock pulses. The rotational speed, direction, and amount of movement of M11 is determined by the increment of the driving step count. This count is reset each time PS61 (scanner HP) is turned ON or OFF by the exposure unit. Movement speed of the exposure unit Scanning speed Operation mode Scan Return Home position search Movement speed 320 mm/s (1:1) 640 mm/s 247 mm/s
Read with shading correction Shading correction is performed in different ways depending on whether SW2 (sub power) is ON or the START button is ON. When shading correction starts, the exposure unit is at the home position and PS61 (scanner HP) is OFF. (1) When SW2 (sub power) is ON L1 (exposure lamp) turns ON. Next, M11 (scanner) moves the exposure unit toward the paper exit side. After being driven by the specified number of steps, M11 stops, thus reading the light reflected by the white reference plate installed underneath the glass stopper plate and performing the first white correction. Next, M11 moves the exposure unit toward the paper exit side. After being driven by the specified number of steps, M11 performs the second white correction. Then, L1 is turned OFF for black correction, searching for the home position of the exposure unit. In each of the first and second shading correction processes, the CCD 1 line data is read to compare brightness levels between pixels. The brighter data is used as white correction data.
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e. PS61 Platen APS read position
First white correction Second white correction Black correction

Home position search

ADF copy operation After completion of the shading correction started by pressing the START button, M11 (scanner) moves the exposure unit toward the paper exit side. After being driven by the specified number of steps from the position where PS61 (scanner HP) was turned ON, it stops. This position is the exposure position for ADF copy operation. Then, ADF copy operation is performed. After completion of the ADF copy operation, L1 (exposure lamp) is turned OFF to start searching for the exposure unit home position. PS61 Platen APS read position

(2) When the START button is ON L1 (exposure lamp) turns ON. Next, M11 (scanner) moves the exposure unit toward the paper exit side. After being driven by the specified number of steps, M11 (scanner) stops, thus reading the light reflected by the white reference plate installed underneath the glass stopper plate and performing the first white correction. Next, M11 moves the exposure unit toward the paper exit side. After being driven by the specified number of steps, M11 performs the second white correction. Then, M11 proceeds to the ADF copy operation or platen copy operation.
First white correction Second white correction
Home position search Original read position
chapter2_C.fm Page 4 Friday, November 1, 2002 2:08 PM
Platen copy operation Platen copy operation is performed in different ways depending on whether AE control is performed. After completion of the shading correction started by pressing the START button, AE scanning is performed in the paper feed direction if the AE mode has been selected. Then, exposure scanning is performed at the speed corresponding to the specified magnification by the distance corresponding to the original size, thus searching for the home position.
a. Input signals (1) SIG/SCANHP_PS (PS61 to SCDB to PRCB) Scanner home position detection signal The reference position of the home position of the exposure unit is detected. [L]: The exposure unit is detected. [H]: The exposure unit is not detected. b. PRCB output signal (1) SCAN_CLK (PRCB to SCDB) M11 (scanner) clock signal (2) SCAN_F/R (PRCB to SCDB) M11 (scanner) rotational direction switchover signal [L]: The exposure unit is moved toward the paper exit side. [H]: The exposure unit is moved toward the paper feed side. (3) MODE1 to 3 (PRCB to SCDB) M11 (scanner) energize switchover signals (4) SCAN_CUR1 to 3 (PRCB to SCDB) M11 (scanner) energize current switchover signals c. SCDB output signals (1) U, V, W (SCDB to M11) M11 (scanner) drive control signals These signals are used to control rotation of M11 (scanner). By supplying and stopping clock pulses, the motor is turned ON/OFF and the rotational direction is switched.

Transfer

Separation
chapter2_F.fm Page 2 Friday, November 1, 2002 2:12 PM

[3] Charging Control

C.CONT EM(C).SIG TXD CLK LATCH

CHARGING

The current output to the charging wire and the voltage applied to the grid are supplied from HV (high voltage unit) and they are controlled by PRCB (printer control board). The levels of outputs to these are transmitted using 8-bit serial data. This serial data includes the level information for all outputs driven by HV, excluding the ON/OFF control signal. Accordingly, a separate signal line is provided to turn ON/OFF only the charging wire output and the grid output at the same time.
b. Output signals (1) C.CONT (PRCB to HV) This signal turns ON/OFF the charging wire. [L]: Charging voltage ON [H]: Charging voltage OFF (2) TXD (PRCB to HV) Output level of each high voltage electrode. Serial data signal for control (3) CLK (PRCB to HV) Clock signal for TXD (4) LATCH (PRCB to HV) Latch signal for TXD
a. Charging A Scorotron charging method is used. 24 VDC supplied from DCPS is raised to a negative DC voltage which is then discharged after being applied to the charging wire. Charge output range: -600 A to -1200 A Grid voltage The grid voltage is output from HV to the charging plate. Grid voltage output range: -500 V to -1000 V
a. Input signal (1) EM (C).SIG (HV to PRCB) This signal indicates the leak or short state of the charging corona unit. [L]: Normal [H]: Abnormal
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[4] Transfer/Separation Control
T.CONT EM(T).SIG S.CONT EM(S).SIG TXD CLK LATCH

TRANSFER

SEPARATION
The voltages applied to the transfer wire and separation wire is supplied from HV (high voltage unit) and are controlled by PRCB (printer control board). The levels of outputs to these wires are transmitted using 8-bit serial data. This serial data includes the level information for all outputs driven by HV, excluding the ON/OFF control signal. Accordingly, a separate signal line is provided to turn ON/OFF only the transfer wire or separation wire.
a. Transfer Positive DC high voltage is used for transfer. Transfer DC output range: 50 A to 600 A Separation AC high voltage and negative DC voltage are used for separation. Separation AC output range: 4kV to 5.7kV Separation DC output range: 0 A to -400 A

Application of the developing bias voltage starts after a lapse of the specified time from turning ON of the START button, and stops after a lapse of the specified time from turning OFF of PS43 (leading edge) by the last copy paper. Developing bias output range: -300 V to -700 V
a. Output signal (1) B.CONT (PRCB to HV) Developing bias output ON/OFF control signal. [L]: Developing bias ON [H]:Developing bias OFF
chapter2_G.fm Page 4 Friday, November 1, 2002 2:13 PM

[5] Dmax Control

5V 12V P.GND A.GND DMLED CONT DRUM CONT DRUM CLK DM MONI EX CW/CCW DJLED CONT DRUM EM DM SIG EX DRUM JSIG EX TNLED REF TEMP 3.3V2

12V2 S.GND 24V2 P.GND

MS1 MS2
Dmax control is performed by TCSB (toner control sensor board), M2 (drum), M3 (developing), and so on under the control of PRCB (printer control board).
The purpose of Dmax control is to adjust the maximum density to the reference level for each machine.
a. Dmax control (1) Method Several latent images are created at the maximum laser power, images are developed with the rotational speed of the developing sleeve varied, then each density is read by the Dmax sensor (PD1) on TCSB (toner control sensor board). The developing sleeve speed detected when the density has reached the reference level is recorded as the optimum sleeve speed, allowing developing to be performed at this sleeve speed. (2) Timing a) When the fixing temperature is lower than 50C at SW2 (sub power) ON b) Every 10,000 prints, upon completion of the last job.
chapter2_G.fm Page 5 Friday, November 1, 2002 2:13 PM
a. Input signals (1) DM_SIG_EX (TCSB to PRCB) Output voltage of Dmax detection sensor (PC1) on TCSB (toner control sensor board) Reference voltage: 2.5 V (2) DM_MONI_EX (TCSB to PRCB) This signal monitors the light reflected by the drum surface (without toner). The voltage applied to the Dmax detection LED is corrected by TNLED_REF so that the output voltage becomes 1.9 V (calibration). Reference voltage: 1.9 V <Timing> Before Dmax correction (3) DRUM_JSIG_EX (TCSB to PRCB) This signal detects a jam caused by paper wrapping around the drum. A jam is detected when the voltage becomes 4.0 V or more. (4) TEMP, 3.3V2 (TCSB to PRCB) Drum temperature detection signal b. Output signals (1) DMLED CONT (PRCB to TCSB) Dmax LED ON/OFF control signal [L]: LED ON [H]: LED OFF (2) TNLED_REF (PRCB to TCSB) Power supply line for PD1 LED on TCSB. The voltage is adjusted so that the Dmax MONI signal becomes 1.9 V. (3) DJLED_CONT (PRCB to TCSB) JAM LED ON/OFF control signal [L]: LED ON [H]: LED OFF
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[6] Gradation Correction Control
12V A.GND G SIG EX LED CONT TNLED REF 5V P.GND DRUM CONT DRUM CLK CW/CCW DRUM EM

[3] Toner Level Detection Control
S.GND TONER SIG T SENSE CONT 5V P.GND TONERM CONT TONERM CLK TONERM CW/CCW TONERM EM

M13 MS2

90 rotation
To agitation/conveyance block of toner supply unit
Toner level detection is controlled by the TLD (toner level detection sensor) and the PRCB (printer control board).
a. Toner level detection A piezoelectric device is used as the TLD (toner level detection sensor). When the level of toner in the hopper becomes low, the toner supply signal is output to PRCB (printer control board). As a result, a message is displayed on the LCD connected to OB1 (operation board/1). Detection timing The detection timing is as follows: Power-on When the front door opens or closes During copying Toner supply to toner supply unit When the no toner state is detected by TLD (toner level detection sensor), M13 (toner bottle) is turned ON to supply toner from the toner cartridge to the toner supply unit. Detection of no toner state in toner cartridge If the no toner state is detected by TLD (toner level detection) after M13 has been held ON for a specified period of time, the toner cartridge is assumed to be empty.
chapter2_H.fm Page 3 Friday, November 1, 2002 2:15 PM
a. Input signals (1) TONER_SIG (TLD to PRCB) When the level of toner in the toner supply unit becomes low, this signal goes low ([L]), displaying a message on the LCD connected to OB1 (operation board/1). (2) TONERM_EM (M13 to PRCB) M13 (toner bottle) abnormality detection signal [L]: M13 is normal. [H]: M13 is abnormal. b. Output signals (1) T_SENSE_CONT (PRCB to TLD) TLD (toner level detection sensor) power control signal The TLD is powered only when it is detecting the toner level. (2) TONERM_CONT (PRCB to M13) M13 (toner bottle) control signal [L]: M13 ON [H]: M13 OFF (3) TONERM_CLK (PRCB to M13) M13 (toner bottle) rotation speed control clock signal (4) TONERM_CW/CCW (PRCB to M13) M13 (toner bottle) rotational direction indication signal [H]: CW direction rotation [L]: CCW direction rotation
[4] M12 (Toner Supply) Control
TNSM24V TNSM24V TNSM A TNSM AB TNSM B TNSM BB 12V A.GND DMLED CONT DM MONI EX DJLED CONT DM SIG EX DRUM JSIG EX TNLED REF
M12 (toner supply) is controlled by the PRCB (printer control board). Toner density is detected by TCSB (toner control sensor board).
a. Toner density detection The Dmax sensor (PD1) on the TCSB (toner control sensor board) detects the density of the toner control patch developed on the drum surface to output the signal corresponding to the detected density to PRCB (printer control board).
chapter2_H.fm Page 4 Friday, November 1, 2002 2:15 PM
Toner supply When the voltage detected by TCSB (toner control sensor board) is below the specified value, PRCB issues a control signal to drive M12 (toner supply). The relationship between the paper size and toner supply time is summarized in the following table: Paper size A3 B4 F4 A4 B5 B5R AX 17 8.5 X 14 8.5 X 11 5.5 X 8.5 Supply time (sec) 1.30 0.98 0.98 0.65 0.49 0.49 0.33 1.30 0.98 0.65 0.49

Caution: Trays 1 and 2 have the same shape and mechanisms.
Mechanism Paper lift-up *1 Method Up: Driven by wires Down: Falls down by its own weight Front loading Torque limiter Paper feed roller Photosensor + Actuator
Tray loading Double feed prevention 1st paper feed No paper detection
Paper lift-up a) Hoisting of up/down plate Paper feed trays are driven by wires. When a paper tray is loaded, the tray up drive motor/ 1(M16)/2(M17) rotates to wind the wires around the drive pulleys and consequently the up/down plate in the tray moves up. When the tray upper limit PS/1(PS2)/2(PS8) detects the actuator of the roller that has been moved up by paper, the tray up drive motor/1(M16)/ 2 (M17) stops.
Paper size detec- Width: VR Length: Photosensor + tion *2 Actuators (two) (Universal) Photosensor + Actuator 1st paper feed paper loop mech- + clutch anism*3
chapter2_J.fm Page 2 Friday, November 1, 2002 2:18 PM
b) Lowering of tray When the paper feed tray is pulled out, the coupling shaft of the tray is disengaged from the coupling gear of the tray up drive motor on the main body side, allowing the up/down plate in the tray to fall down by its own weight. [Main body side] Coupling gear
1st paper feed paper loop mechanism When paper feed starts, paper is fed to the preregistration roller by the feed roller and paper feed rollers. The fed out paper operates the actuator of the paper feed PS/1 (PS1), the paper feed PS/2 (PS7) turning it ON. The feed and paper feed rollers remain ON for a specified time after the actuation of the paper feed PS/1 (PS1) and PS/2 (PS7) causing a paper loop to form against the pre-registration rollers which are not turning. In this way paper skew is corrected.

Coupling [Tray side]

Paper size detection Length: When paper pushes the paper size detection actuator, the paper size PS/21/2-2 (PS6/PS12) and the paper size PS/1-1/1-2 (PS5/PS11) turn ON. Thus, the paper size is automatically determined according to the combination of the ON/OFF states of these PSs. Width: When the side guides of the tray are slid, the rack gear of the side guide (front) turns the paper size VR/1/2 gear. Thus, the paper size is automatically determined according to the change in the resistance value of the VR.

1. 2. 3. 4.

Feed roller Paper feed roller Paper feed PS/1(PS1), /2 (PS7) Pre-registration roller
Paper size VR gear Rack gear Side guide (front)
chapter2_J.fm Page 3 Friday, November 1, 2002 2:18 PM
[3] First Paper Feed Control

MC24V_1 T1PREMC_DRV

MC4 PS1

Tray 1

FEEDM_CONT FEEDM_CLK FEEDM_F/E FEEDM_EM 5V P.GND
5V3 T1PRE_PS SGND MC24V_1 C MC24_1 T2PREMC_DRV 5V3 T2PRE_PS SGND

MC5 MC6 PS7 Tray 2

Paper fed from tray 1 is then fed to the second paper feed unit directly without passing through vertical conveyance rollers. When paper is fed from tray 2 or 3, PS26 (vertical conveyance/2) is used to feed paper to the standby position. When PS26 is turned OFF by the preceding paper, MC11 and MC12 (vertical conveyance MC/1 and MC/2) are turned ON and the paper fed from tray 2 or 3 is fed to the standby position (where PS26 was turned ON) by the drive force of M1 (paper feed). MC11 and MC12 are turned ON after lapse of the specified time from restart of registration of the preceding paper to rotate all vertical conveyance rollers, thus feeding paper to the second paper unit.
a. PRCB input signals (1) T1PASS_PS (PS25 to PRCB) Paper passage detection signal (for tray 1) [L]: Not detected. [H]: Detected. (2) T2PASS_PS (PS26 to PRCB) Paper passage detection signal (for tray 2) [L]: Not detected. [H]: Detected. (3) T3PASS_PS (PS27 to PRCB) Paper passage detection signal (for tray 3) [L]: Not detected. [H]: Detected. (4) VF_DOOR_PS (PS29 to PRCB) Vertical conveyance section open/close detection signal [L]: Open [H]: Closed b. PRCB output signals (1) VFMC1_DRV (PRCB to MC11) MC11 drive control signal [L]: MC11 ON [H]: MC11 OFF (2) VFMC2_DRV (PRCB to MC12) MC12 drive control signal [L]: MC12 ON [H]: MC12 OFF
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1. 2. 3. 4. 5. 6. 7. ADU conveyance roller 1 ADU conveyance roller 2 Conveyance belt Pre-transfer roller Registration roller ADU pre-registration roller ADU conveyance roller 4
8. 9. 10. 11. 12. 13. 14.
ADU conveyance roller 3 ADU reverse roller ADU gate Reverse/exit roller Reverse/exit gate Paper exit conveyance roller Paper exit roller
1. 2. 3. 4. 5. 6. 7. 8. 9. Paper exit roller rotation knob Paper exit motor (M7) Paper exit fan/R (FM7) Paper exit fan/F (FM6) Reverse gate SD (SD7) Reverse/exit motor (M8) TSL Conveyance motor (M5) Transfer/separation cleaning motor (M10) 10. 11. 12. 13. 14. 15. 16. 17. ADU deceleration MC (MC2) ADU conveyance MC (MC13) ADU drive board (ADUDB) Reverse/exit roller rotation knob Mis-centering PS (PS70) Paper dust cleaning brush Registration MC (MC1) Registration roller rotation knob
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<ADU> Registration roller Loop formation point
ADU pre-registration roller *2 Image position correction A leading edge PS (PS43) and paper mis-centering PS (PS70) are provided at the exit of the registration roller, thus enhancing the positional accuracy of the copy image. The paper position information detected by PS43 and PS70 is processed by the image processor to correct the image write position in such a manner that the document (scanned image) position match the copy paper position. The leading edge PS (PS43) is used to correct the write position in the sub-scanning direction, and the mis-centering PS (PS70) is used to correct the write position in the main scanning direction.

<By-pass tray>

1. 2. 3. 4. 5. 6. 7. 8. Loop formation point Feed roller (LCT) Vertical conveyance roller (upper) Loop roller Registration roller Loop formation point Feed roller Registration roller
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Second paper feed auxiliary mechanism The distance between the registration roller and the transfer and separation corona unit is made long to achieve the time required for correcting the image position. To assist conveyance of paper between the registration roller and the image transfer and separation corona unit, a pretransfer roller is provided just before the transfer and separation corona unit.
Leading edge PS (PS43) (rear) Paper mis-centering PS (PS70) (front) Registration roller Pre-transfer roller Transfer and separation corona unit
Conveyance section paper suction mechanism A paper suction duct is provided in the middle of the conveyance section and is led to the conveyance suction fan (FM3) installed in the ADU. To improve transportability of the paper that passes through the conveyance section, the conveyance suction fan is used to provide suction for the paper.
Reverse/exit paper path selection The reverse/exit selection gate in the fixing unit determines whether the paper is to be ejected straight or reversed and ejected. The paper gate is operated by the reverse gate SD (SD7) installed in the ADU. Because paper is reversed in the reverse/exit section in the ADU, the reverse/exit section is provided with a reverse/exit gate to switch between the forward and backward paper conveyance paths. This gate has no drive mechanism and it is opened by the rigidity of the paper. Reverse/exit operation Normally, the reverse/exit selection gate opens when the reverse gate SD (SD7) is turned OFF. The paper fed by the exit roller in the fixing unit is fed, through the path under the reverse/exit selection gate, to the reverse/exit section in the ADU by the decurler roller. Normally, the reverse/ exit gate in the reverse/exit section is closed. This gate is opened by the rigidity of the fed paper, allowing the paper to be fed to the reverse/ exit roller, ADU gate, and ADU reverse roller sequentially. Normally, the ADU gate is closed and it has no drive mechanism; it is opened by the rigidity of paper. When the paper reverse PS (PS42) detects the trailing edge of paper and consequently turns OFF, the reverse/exit roller and ADU reverse roller start rotating in the opposite direction, feeding the paper back toward the fixing unit. However, since the reverse/exit gate is closed, the paper is fed to the main body exit roller via the path outside this gate. Thus, the paper is ejected with the print side down.

5V2 24V1 S.GND

24V2 P.GND 24V1 5V2 S.GND P.GND
a. Input signals (1) MAINEXIT_PS (PS37 to PRCB) Main body exit section paper passage detection signal [L]: Detected. [H]: Not detected. (2) SUC_EM (FM3 to ADUSDB) FM3 (conveyance suction) fault detection signal [L]: FM3 is normal. [H]: FM3 is abnormal. b. Output signal (1) MAINEXIT_PS (ADUDB to FM3) FM3 (conveyance suction) drive signal [L]: FM3 OFF [H]: FM3 ON
The paper fed from the second paper feed section is fed to the fixing unit by the pre-transfer roller and conveyance belt driven by M5 (conveyance). In the conveyance section, paper suction is provided by FM3 (conveyance suction) through the duct installed on the back of the conveyance belt. M5 and FM3 are controlled by PRCB (printer control board) via ADUDB (ADU drive board).
a. M5 (conveyance) operation M5 (conveyance) starts when the START button is pressed, and it stops when the PS37 (paper exit) turns OFF at detection of the trailing edge of the last sheet of paper. FM3 (conveyance suction) operation FM3 is turned ON/OFF in sync with M2 (drum).
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[5] Paper Reverse and Exit Control
5V P.GND MAINM CONT MAINM CLK MAINM F/R MAINM EM 24V 24V A /A B /B 5V2 FIXEXIT PS S.GND 5V MAINEXIT PS S.GND 24V 24V A /A B /B 24V 24V A /A B /B 5V2 DECUR PS S.GND 5V2 ADU REV S.GND
IO DTXD IO DCLK ADU LATCH IO UCLK REQ1 IO URXD ACK1 ERR OUT1 2NDM CLK

PS42 PS45 PS46 SD7

5V2 REV PS S.GND 24V2 GATE DR
The reserve/exit selection gate in the fixing unit determines whether the paper fed from the fixing unit is to be ejected straight or reversed. The reverse/exit selection gate is driven by SD7 (reverse gate). The decurler roller is driven by M4 (fixing) and the reverse/exit roller is driven by M8 (reverse/exit). The ADU reverse roller is driven by M9 (ADU reverse). The exit conveyance roller and main body exit roller are driven by M7 (paper exit).
M4 and M7 are controlled by PRCB (printer control board) directly. M8, M9, and SD7 are controlled by PRCB (printer control board) via ADUDB (ADU drive board). Related signals are PS30 (fixing exit), PS37 (paper exit), and PS42 (paper reverse).

2-N-10

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a. Reverse/exit selection gate control The reverse/exit selection gate is driven by SD7 (reverse gate). Normally, the reverse/exit selection gate is open to guide paper to the reverse/ exit section in ADU. When paper is ejected straight, SD7 is turned ON to close the reverse/ exit selection gate. When paper is ejected straight, SD7 is turned ON when the START button is pressed and it is turned OFF when PS37 (paper exit) turns OFF at detection of the trailing edge of the last sheet of paper. M4 (fixing) control M4 (fixing) starts when the START button is pressed, and it stops when PS37 (paper exit) turns OFF at detection of the training edge of the last sheet of paper. Straight paper exit Paper is fed to the paper exit section straight by the paper exit roller driven by M4 (fixing) because SD7 (reverse gate) is turned ON to close the reverse/exit selection gate. Paper reverse/exit Because SD7 (reverse gate) has been turned OFF to open the reverse/exit selection gate, paper is fed to the reverse/exit section in ADU by the paper exit roller and decurler roller driven by M4 (fixing). ADU conveyance Same as paper reverse/exit. Reverse control M8 (reverse/exit) starts when the START button is pressed, and it stops when PS37 (paper exit) turns OFF at detection of the trailing edge of the last sheet of paper. Its rotational speed and direction change when paper is ejected or reversed, or is fed to ADU. Paper reverse/exit The paper fed from the fixing unit is then fed to the reverse/exit section via the reverse/exit selection gate. Normally, M8 and M9 are rotating in the forward direction at a low speed, feeding the paper to the ADU reverse section. When PS30 (fixing exit) detects the trailing edge of paper and consequently turns OFF, M8 and M9 start rotating in the forward direction at a high speed, feeding paper to the ADU reverse section continuously. When PS42 (paper reverse) detects the trailing edge of paper and conse2-N-11

Decurler The paper guided by the reverse/exit selection gate is decurled while it passes between the decurler roller and restriction shafts. The decurler roller is driven by the fixing roller (upper) via gears. Fixing roller (upper)

Restriction shafts

Decurler roller *4 Jam detection When a jam occurs in the fixing exit section, the paper exit guide plate (lower) is pressed down, causing the fixing exit PS (PS30) to detect a jam via the jam detection plate and actuator.
1. 2. 3. 4. 5. Pressure roller Cleaning web unwinding shaft Web SD (SD2) Ratchet Cleaning web wind-up shaft
Actuator Exit guide plate (lower) Fixing exit PS (PS30) Jam detection plate
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[3] M16 (Web Drive) Control
24VDC PGND 5VDC SGND 5V2 FIXEXIT_PS S.GND MC24V_2 WEBSC_DRV
a. PRCB input signal (1) FIXEXIT_PS (PS30 to PRCB) Detection signal of passage of paper at fixing unit exit [L]: Detected. [H]: Not detected. b. PRCB output signal (1) WEBSC_DRV (PRCB to SD2) SD2 (web) drive control signal [L]: SD2 ON [H]: SD2 OFF

PS30 SD2

SD2 (web) is controlled by PRCB (printer control board). The related signal is PS30 (fixing exit).
When PS30 is turned ON by passage of paper, SD2 is controlled by PRCB (printer control board) according to the fixing web counter value. The fixing web counter value is incremented together with the total counter in exit section of the main body. The relationship between the fixing web counter values and SD2 (web) is as follows: Fixing web counter value
1 to 12,000 12,001 to 30,000 30,001 to 60,000 60,001 to 125,000 125,0001 to 260,000 260,001 or more

SD2 drive count

Once per copy Once per copy *1 Once per copy *2 Once per 2 copies Once per 3 copies Once per 6 copies
SD2 is turned ON once per copy, but is not turned ON once per every six copies. SD2 is turned ON once per copy, but is not turned ON once per every three copies.
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