Brother FAX-921- User Manual

I - 1 1. EQUIPMENT OUTLINE 1.1 External Appearance and Weight The figure below shows the equipment appearance and approximate dimensions. Weight: Machine proper (excluding a ribbon cartridge) Approx. 4 kg (8.82 lbs.) In package Approx. 6 kg (13.23 lbs.) 1.2 Components The equipment consists of the f...

I - 2 2. SPECIFICATIONS Model Name FAX750 FAX770 Engine Thermal transfer Thermal transfer Color Black (1395) White (1397) Transmission Speed (sec) 15 15 Modem Speed (bps) 9600 9600 Group Compatibility G3 G3 Input/Output Width 8.5"/8.5" 8.5"/8.5" ADF (pages) 10 10 Recording Paper Load...

CONTENTS 1. OVERVIEW ............................................................................................................... III -1 2. MECHANISMS .......................................................................................................... III -2 2.1 Transmitting Mechanism (Feed...

III - 2 2. MECHANISMS The facsimile equipment is classified into the following mechanisms: n Transmitting Mechanism Feeding and scanning documents n Receiving Mechanism Feeding paper and printing data n Power Transmission Mechanism Switching the power transmission route n Sensors and Actuators 2.1 T...

III - 3 2.1.2 Scanner The scanner uses a contact image sensor (CIS) unit which consists of an LED array illuminatingdocuments, a self-focus lens array collecting the reflected light, a CIS PCB carrying outphotoelectric conversion to output picture element data, and a cover glass on which a documenta...

III - 4 2.2 Receiving Mechanism (Feeding paper and printing data) The receiving mechanism consists of the recording paper cover ASSY, paper feed roller ASSY,platen, thermal recording head, paper ejection roller, and sensors. (For details about the sensors,refer to Section 2.4.) STEP 1: In the paper ...

III - 5 2.3 Power Transmission Mechanism The equipment has a single drive motor whose power transmission route can be switched by theplanetary gear systems and the solenoid. This switching allows the equipment to function in fouroperation modes (scanning, paper feeding/ejecting, recording, and copyi...

III - 6 2.3.2 Description of planetary gear system The equipment uses the following three planetary gear systems: - Sun gear 24/90 ("B" in the figure given on the previous page) and its planet gears - Sun gear 65/60 ("K") and its planet gear - Sun gear 24/28 ("O") and its pla...

III - 7 2.3.3 Power transmission for four operation modes Depending upon the solenoid ON/OFF state and the motor rotation direction, the planetary geartrain switches the power transmission route for the four operation modes. Solenoid ON/OFF state Motor rotation direction

III - 11 Active Gears on the Inner Side of the Drive Unit

III - 14 2.3.4 Power transmission route Rotation of the motor gear is transmitted as shown below. Gears on the outer side of the drive unit and on the left sides ofthe platen frame, main frame and control panel ASSY Gears on the inner side of the drive unit A: Motor gear O: Sun gear 24/28 B: Sun gea...

III - 16 2.4 Sensors and Actuators This equipment has five photosensors and two mechanical switches as described below. Sensor name Type Located on Document front sensor Photosensor Control panel PCB ASSY Document rear sensor Photosensor (PI2) Main PCB Paper-edge sensor Photosensor (PH1) Sensor PCB ...

III - 19 3. CONTROL ELECTRONICS 3.1 Configuration The hardware configuration of the facsimile equipment is shown below. *1 On the main PCB are these sensors: l Ribbon sensor (PI1) l Document rear sensor (PI2) l Cover sensor (SW1) *2 On the front document sensor PCB is the front document sensor. *3 O...

III - 20 3.2 Main PCB The main PCB, which is the nucleus controlling the entire operation of the equipment, consists of aFAX engine (ASIC), memories, motor drive circuitry, sensor detection circuitry, and analog circuitsfor scanning, recording, and power transmission shifting. *Provided on the FAX87...

III - 22 3.3 NCU PCB The NCU PCB switches the communications line to telephone or built-in MODEM, under the controlof the main PCB. U.S.A. versions

III - 24 3.4 Control Panel PCB The control panel PCB and the main PCB communicate with each other by serially transmittingcommands and data. The control panel unit consists of a gate array, an LCD and LEDs, which are controlled by the gatearray according to commands issued from the FAX engine on the...

III - 25 3.5 Power Supply PCB The power supply uses the switching regulator to generate DC power (+25V, +6.5V, and +5V) froma commercial AC power line. The +25V source is stabilized and fed to the motor and solenoid (for feeding documents, recordingpaper, and ink ribbon), recording head, the main PC...

CHAPTER IV . DISASSEMBLY/REASSEMBLY, LUBRICATION AND ADJUSTMENT

IV - 1 1. DISASSEMBLY/REASSEMBLY n n Safety Precautions To prevent the creation of secondary problems by mishandling, observe the following precautionsduring maintenance work. (1) Unplug the power cord from the power outlet before replacing parts or units. When having access to the power supply, be ...

IV - 2 Tightening Torque List Location Screw type Q'ty Tightening torque Loosening torque (kg•cm) (kg•cm) ADF parts Taptite, pan (washer) B M3x6 1 4 ±2 Min. 1 Panel rear cover Taptite, cup B M3x8 2 4 ±2 Min. 1.5 Document front sensor PCB Taptite, cup B M2.6x6 1 4 ±2 Min. 1 Control panel PCB* Taptite...

IV - 3 n n Preparation Prior to proceeding to the disassembly procedure, (1) Unplug - the modular jack of the telephone line,- the modular jack of the curled cord (and remove the handset), and- the modular jack of an external telephone set if connected. (Not shown below.) (2) Remove - the document w...

IV - 5 1.1 ROM Cover, Battery ASSY* and Ribbon Shaft Stopper (*FAX870MC/FAX-930/FAX-931/MFC970MC) (1) Open the control panel ASSY to the front. (2) Pull up the lock levers and open the recording paper cover ASSY to the rear. (3) As shown below, insert the tip of the spring hook at the center or righ...

IV - 6 (5) Remove the ribbon shaft stopper by pushing down the rear end of the stopper lightly with a screwdriver. n n Reassembling Notes • When reinstalling the ribbon shaft stopper, lightly push down the ribbon shaft stopper spring withthe rear end of the ribbon shaft stopper and then set the stop...

IV - 7 1.2 Control Panel ASSY (1) Open the control panel ASSY to the front. (2) Push the right arm of the panel rear cover outward (in the direction of arrow • ) to release it from the boss provided on the main frame, then move the control panel ASSY to the left andpush the left arm outward (in the ...

IV - 9 1.3 Panel Rear Cover and Control Panel (1) Place the control panel ASSY upside down. If you do not need to remove the ADF parts, document pressure bar, or document ejectionroller, skip to step (6). (2) To remove the ADF parts (spring covers, spring plates, and separation rubber), remove the s...

IV - 14 1.4 LF Roller ASSY and CIS Unit (1) Take off the LF leaf spring by removing the screw. (2) Push the arm rib to the rear and shift the LF roller ASSY to the left. The bearing also comes off.

IV - 22 1.6 Recording Paper Cover ASSY and Paper Guides* ( * Not provided on the U.S.A. and Canadian versions.) (1) To remove the paper guides*, open the paper front cover towards you, then pull up the latch (in the direction of arrow • in the illustration below) and pull the paper guide in the dire...

IV - 34 1.8 Cover Stopper and Platen Frame ASSY TIP: Only when you need to remove the platen frame from the main frame, remove the cover stopper. When accessing other components, keep the cover stopper in place for easier handling. (1) Remove the screw from the cover stopper. (2) Lift up the rear en...

IV - 36 1.9 Bottom Plate (1) Place the machine upside down. (2) Remove the seven screws from the bottom plate. (3) Slightly lift up the bottom plate and disconnect the grounding terminal. (4) Remove the bottom plate together with the insulation sheet.

IV - 43 1.14 Cover Sensor Actuators and Pinch Roller (1) Pull up the cover sensor actuator A and turn it to separate from the actuator B. The spring pops up and the actuator B drops. (2) Remove the harness guide film. NOTE: This film is attached to the main frame with double-sided adhesive tape. Thi...

IV - 47 2. LUBRICATION Apply the specified lubricants to the lubrication points as shown below. Molykote EM-30L or EM-30LG For points , apply a rice-sized pinch of grease (6 mm 3 ). Floil GE-334C For points , apply half of a rice-sized pinch of grease (3 mm 3 ). [ 1 ] Control panel ASSY

IV - 49 [ 2 ] LF roller ASSY [ 3 ] Platen frame ASSY

V - 1 1. ENTRY INTO THE MAINTENANCE MODE FAX750/FAX770/FAX870MC/MFC970MC: To make the facsimile equipment enter themaintenance mode, press the Function , * , 2 , 8 , 6 , and 4 keys in this order. Within 2 seconds FAX-910/FAX-920/FAX-921/FAX-930/FAX-931/MFC-925: To make the facsimile equipment entert...

V - 4 3. DETAILED DESCRIPTION OF MAINTENANCE-MODE FUNCTIONS 3.1 EEPROM Parameter Initialization n n Function The equipment initializes the parameters, user switches, and firmware switches registered in theEEPROM, to the initial values. Entering the function code 01 initializes all of the EEPROM area...

V - 11 n n Detailed Description for the Firmware Switches WSW01 (Dial pulse setting) Selector No. Function Setting and Specifications 1 2 Dial pulse generation mode No. 1 2 0 0 : N 0 1 : N+1 1 0 : 10-N 1 1 : N 3 4 Break time length in pulse dialing No. 3 4 0 0 : 60 ms 0 1 : 67 ms 1 0 : 40 ms (for 16...

V - 42 WSW29 (Function setting 7) Selector No. Function Setting and Specifications 1 | 3 Compression threshold level forvoice signals inputted via thetelephone line in the built-in TADoperation No. 1 2 3 0 0 0 : -47.0 dBm (A) 0 0 1 : -48.5 dBm (B) 0 1 0 : -50.0 dBm (C) 0 1 1 : -51.5 dBm (D) 1 0 0 : ...

VI - 1 1. ERROR INDICATION To help the user or the service personnel promptly locate the cause of a problem (if any), thefacsimile equipment incorporates the self-diagnostic functions which display error messages forequipment errors and communications errors. For the communications errors, the equip...

VI - 5 1.2 Communications Errors If a communications error occurs, the facsimile equipment emits an audible alarm (intermittent beeping) for approximately 4 seconds, displays the corresponding error message, and prints out the transmission verification report if the equipment is in sending operation...

VI - 10 (9) Signal isolation Code 1 Code 2 Causes 90 01 Unable to detect video signals and commands within 6 secondsafter CFR is transmitted. 90 02 Received PPS containing invalid page count or block count. (10) Video signal reception Code 1 Code 2 Causes A0 03 Error correction sequence not terminat...

VI - 12 2. TROUBLESHOOTING 2.1 Introduction This section gives the service personnel some of the troubleshooting procedures to be followed ifan error or malfunction occurs with the facsimile equipment. It is impossible to anticipate all of thepossible problems which may occur in future and determine...

VI - 13 2.4 Troubleshooting Procedures [ 1 ] Control panel related Trouble Check: (1) LCD shows nothing. • Panel-main harness between the main PCB and the control PCB • Interfaces between the main PCB, NCU PCB and power supply PCB • LCD • Control panel PCB • Power supply PCB • Main PCB (2) Control p...

FAX750/FAX770/FAX870MC FAX860/FAX880/FAX1270T FAX-910/FAX-920/FAX-921/FAX-930/FAX-931 FAX-917/FAX-940 MFC-925/MFC970MC/MFC1970MCT Appendix 1. EEPROM Customizing Codes

EEPROM Customizing Codes This function allows you to customize the EEPROM according to language, function settings, andfirmware switch settings. The customizing codes list is given on the next page. n Operating Procedure (1) FAX750/FAX770/FAX860/FAX870MC/FAX880/FAX1270T/MFC970MC/MFC1970MCT: Within 2...

FAX750/FAX770/FAX870MC FAX860/FAX880/FAX1270T FAX-910/FAX-920/FAX-921/FAX-930/FAX-931 MFC-925/MFC970MC/MFC1970MCT Appendix 2. Circuit Diagrams A. Main PCB B. Network Control Unit (NCU) PCB C. Control Panel PCB D. Power Supply PCB

I T E M L 1 S P 3 S P 1 C 8 P H 3 S P 5 S P 9 S P 7 S P 6 S P 4 S P 1 1 S P 1 5 S P 1 3 S P 1 2 S P 1 0 U G 6 7 1 1 - 0 X X U G 6 7 1 2 - 0 X X P C 2 5 0 B 1 0 5 P C 2 5 0 B 1 0 5 R C H 8 5 5 - 3 3 2 K R C H 8 5 5 - 3 3 2 K 5 m m J U M P E R 5 m m J U M P E R 5 m m J U M P E R 5 m m J U M P E R 5 m ...

FACSIMILE EQUIPMENT PARTS REFERENCE LIST MODEL: FAX-910/920/921/930/931/940 MFC-925 (For Germany / United Kingdom / France /Australia / Norway / Belgium / Netherlands /Switzerland / Ireland / Finland / Denmark /Austria / Spain / Italy / Israel / Sweden / New Zealand / Czechoslovakia / Euro Generic) ...

NOTES FOR USING THIS PARTS REFERENCE LIST 1. In the case of ordering parts, it needs mentioning the following items: (1) Code (2) Q' ty (3) Description Note: No orders without Parts Code or Tool No. can be accepted. [Example] (1) (2) (3) REF.NO. CODE Q' TY DESCRIPTION REMARKS 2. Parts change will be...