Canon NP-70, Service Manual

Page 1: ...CANON SERVICE MANUAL NP 70 Total Guaranty System L c CANON INC ...

Page 2: ...CANON SERVICE MANUAL NP 70 CANON INC ...

Page 3: ...adjustments proce dures tolerances etc are satisfied Also for the convenience of the service technician circuit diagrams and layouts have been appended in the rear of the manual This service manual is written with the intent that it be applicable to all NP 70 copiers regardless of product number Thus any section which deals with a specific product numbers is identified This manual contains informa...

Page 4: ... CYLINDER 4 24 4 5 1 1 becomes approx 1800 100 volts becomes approx 1800 50 bolts 4 5 2 Table 4 1 Corona Wire Specifications Standard High 16 5 0 5 9 5 0 5 Standard Hight about 16 5 refer to Table about 9 5 refer to Table 4 26 2 Perform the replacement Assembly as follows O Perform the replacement Assembly and Transfer Corona Assembly as follows O Addition Paper Guide Wire Replacement of Transfer ...

Page 5: ...on Sprocket A O Tension Sprocket A O O O O _ O O O O O Tension Sprocket B Chain Drive Sprocket Chain Drive S rocket P 4 71 Fig 4 83 Up down Actuation Lever O Up down Actuation 4 104 d in the rest button and the arm tripping the micro switches moving upward in the rest button is pushed up by the lever and the arm tripping the micro switches move upward B 4 A T R Circuit O C 3 O NFB4 X62 1047 125VAC...

Page 6: ...er Loading of Paper Cassette 1 7 1 5 IMAGE FORMING PROCESS OF THE NP 70 1 8 2 OUTLINE OF NP 70 OPERATION 2 1 BREAKDOWN OF THE NP 70 2 1 2 2 PARTS NOMENCLATURE 2 3 2 3 OUTLINE OF MAIN ASSEMBLIES 2 5 2 3 1 Copyboard Assembly 2 5 2 3 2 Illumination Assembly 2 5 2 3 3 Optical Assembly 2 5 2 3 4 Drum Assembly 2 5 2 3 5 Corona Assemblies 2 5 2 3 6 Developer Assembly 2 6 2 3 7 Drum Cleaner Assembly 2 6 2...

Page 7: ...Feed Interval 3 33 3 3 4 First Feed Interval 3 34 3 3 5 Prestart Time 3 34 3 3 6 Copying Cycle 3 34 3 3 7 Second Feed Interval 3 35 3 3 8 Neutral Time 3 35 3 3 9 STANDBY 3 35 3 4 OUTLINE OF ELECTRICAL COMPONENTS AND CIRCUITS 3 39 3 4 1 Switchable Taps for AC Line Voltage Compensation 3 39 3 4 2 AC Line Voltage Filter 3 39 3 4 3 Rectification Circuit Card 3 39 3 4 4 Rapid Start Illumination Circuit...

Page 8: ...mponents 4 20 4 4 3 Removal Installation Actions 4 22 4 4 4 Repair Servicing Actions 4 23 4 5 CORONA ASSEMBLIES 4 24 4 5 1 Outline of Assembly Operation 4 24 4 5 2 Assembly Main Components 4 24 4 5 3 Removal Installation Actions 4 25 4 5 4 Repair Servicing Actions 4 29 4 6 DEVELOPER ASSEMBLY 4 30 4 6 1 Outline of Assembly Operation 4 30 4 6 2 Assembly Main Components 4 31 4 6 3 Removal Installatio...

Page 9: ...cing Actions 4 78 4 12 PAPER SEPARATING SUBASSEMBLY 4 81 4 12 1 Outline of Assembly Operation 4 81 4 12 2 Assembly Main Components 4 82 4 12 3 Removal Installation Actions 4 83 4 12 4 Repair Servicing Axtions 4 84 4 13 HEATER ASSEMBLY 4 85 4 13 1 Outline of Assembly Operation 4 85 4 13 2 Assembly Main Components 4 86 4 13 3 Removal Installation Actions 4 87 4 13 4 Repair Servicing Actions 4 87 4 1...

Page 10: ... A 4 Photocopier Wiring Diagram Prod No 8 11154 55 1 of 2 A 5 Photocopier Wiring Diagram Prod No 8 11154 55 2 of 2 A 6 Photocopier Wiring Diagram Prod No 8 11156 57 A 7 Photocopier Wiring Diagram Prod No 8 11158 84 A 8 APPENDIX B SPECIFIC CIRCUITS Heater Control Circuit Schematic Diagrams B 1 Printed Circuit Board Layouts 1 of 3 B 2 Printed Circuit Board Layouts 2 of 3 B 3 Printed Circuit Board La...

Page 11: ...gulator 3 40 Original Illumination Circuit 3 41 Heater Wait Control Circuit Associated Components 3 42 Heater Wait Flowchart 3 45 Developer Monitoring Circuitry 3 47 Toner Feed Flowchart 3 48 Developer Low Flowchart 3 48 Developer Temperature Control Circuit Associated Components 3 49 Developer Cooling Flowchart 3 50 Paper Cassette Monitoring Circuitry 3 51 Cassette Empty Flowchart 3 52 Cassette N...

Page 12: ...ion in Copier from copier front 4 22 Fig 428 Drum Unit Reassembly 4 23 Fig 4 29 Eliminator Assembly Removal 4 25 Fig 4 30 Paper Guide Wire Replacement 4 26 Fig 4 31 Corona Wire Loop 4 27 Fig 4 32 Attaching Corona Wire 4 27 Fig 433 Wiring Procedure 4 28 Fig 4 34 Corona Wire Adjustment Positive Corona Assembly Illustrated 4 29 Fig 4 35 Developer Assembly Main Components 4 31 Fig 4 36 ATR Subassembly...

Page 13: ...ation E 4 59 Fig 4 67 Controller Assembly Operation F 4 59 Fig 4 68 Controller Assembly Operation G 4 60 Fig 4 69 Paper Pickup Feeding Operation 4 61 Fig 4 70 Paper Pickup Roller Assembly Main Components 4 62 Fig 4 71 Drive Chain Removal 4 63 Fig 4 72 Timing Roller Drive Main Components 4 64 Fig 4 73 Timing Roller Drive Disassembly A 4 65 Fig 4 74 Timing Roller Drive Disassembly B 4 65 Fig 4 75 Pa...

Page 14: ...r Operation C 4 95 Fig 4 109 Copy Selector Operation D 4 95 Fig 4 110 Stop Button Operation 4 96 Fig 4 111 Drive and Link Stud Positioning 4 96 Fig 4 112 Copy Selector Reassembly 4 97 Fig 4 113 Click and Ratchet Wheel Positioning Top View 4 98 Fig 4 114 Safety Assembly Main Components 4 99 Fig 4 115 Door Switch Group Main Components 4 100 Fig 4116 Door Switch Group Operation A 4 101 Fig 4 117 Door...

Page 15: ...nation of START Flowchart 3 10 Table 3 3 Explanation of COPY Flowchart 3 15 Table 3 4 Explanation of JAM Flowchart 3 28 Table 3 5 Explanation of Heater Wait Flowchart 3 43 Table 3 6 Explanation of Heater Operation Flowchart 3 55 Table 3 7 Voltage Converter Specifications 3 64 Table 4 1 Corona Wire Specifications 4 24 Table 4 2 Adjustment Plate Movement 4 48 Table 4 3 Spring Specifications 4 52 Tab...

Page 16: ...S 1 3 2 PHYSICAL SPECIFICATIONS 1 3 3 PAPER SPECIFICATIONS 1 3 4 COLORS OF PAPER AVAILABLE FROM CANON 1 4 OPERATING PROCEDURES 1 4 1 PREPARATION 1 4 2 PLACING OF ORIGINAL 1 4 3 LOADING OF PAPER 1 4 4 COPYING OPERATIONS 1 4 5 IMAGE DENSITY 1 4 6 HANDLING OF PAPER LOADING OF PAPER CASSETTE 1 5 IMAGE FORMING PROCESS OF THE NP 70 ...

Page 17: ...nch equivalents of Japan Industrial Standard JIS sizes Refer to the specification section for exact dimensions 2 HIGH COPYING SPEED Approximately 15 half size sheets A4 or BS can be copied in one minute 3 DESK TOP COMPACTNESS The NP 70 copier is designed highly compact so that the least amount of space is required As a result large copier performance is obtained from small copier size 4 AUTOMATIC ...

Page 18: ...ccess when something goes wrong with paper feeding Where copied paper is collected Used for opening closing copyboard cover Contains machine controls Number of half size sheets copied is indicated Opened closed when supplying Premix developer and concentrated toner and when cleaning coronas Power is switched on when the red marked side of switch is pressed Lights up when power is switched on Optio...

Page 19: ... under this condition because toner on copy paper will not be sufficiently dry Press for obtaining copies Set the number of copies required to index mark Numbers on copy dial are set to this index mark Adjusts image density Press to stop copy operations during continuous copying Lights up when paper is not properly fed Lights up when paper inside the cassette has been depleted or when the cassette...

Page 20: ...F4 5 minor lens with diaphragm Paper exposure Moving original exposure method Image transfer Corona transfer Image fixing Drying with heat dispersion plate Table 1 1 Performance Specifications of the NP 70 1 3 2 PHYSICAL SPECIFICATIONS Dimensions of body Width Depth Height 83 4 cm 32 7 8 Main body only 125 0 cm 49 3 16 w A3 cassette copyboard in standard position 60 0 cm 23 5 8 34 0 cm 13 3 8 Dime...

Page 21: ...5 x 728 20 3 x 28 7 A3 297 x 420 11 7 x 16 5 B3 364 x 515 14 3 x 20 3 A4 210 x 297 8 3 x 11 7 B4 257 x 364 10 1 x 14 3 AS 148 x 210 5 8 x 8 3 BS 182 x 257 7 2 x 10 1 A6 105 x 148 4 1 x 5 8 B6 128 x 182 5 0 x 7 2 A7 74 x 105 2 9 x 4 1 B7 91 x 128 3 6 x 5 0 A8 52 x 74 2 1 x 2 9 B8 64 x 91 2 5 x 3 6 JIS Table 1 3 Standard of Paper Sizes B4 BS A3 A4 BS A4 A3 Fig 1 3 Original Positioning on Copyboard 1...

Page 22: ...e paper cassette and take off the cassette cover 2 Fan the paper specified copy paper well to separate any sheets which might be stuck to gether 3 Load the paper so that its end is flush to the rear end of the inner plate of the cassette 4 Gently push down the right and left ends of the paper and insert under the separation hooks 5 After loading place the cover on the cassette in an open condition...

Page 23: ...f it is empty replace it 1 4 6 HANDLING OF PAPER LOADING OF PAPER CASSETTE 1 When storing the paper be careful not to expose it to high humidity or direct sunlight 2 Be careful not to fold or wrinkle the paper 3 When loading the paper into the cassette the top sheet of the paper from the marked side of the pack should be the top sheet of the stack in the paper cassette 4 Before loading fan or leaf...

Page 24: ... partial breakdown of the air and ionizes it AC discharge with simultaneous image exposure 2 AC corona discharge and image exposure is applied to the drum surface at the same time Applied voltage 7 0 kVAC on x b o 0 w oa AC corona discharge Positive and negative corona dis charges occur alternately Insulation coating Increases the efficiency of AC corona discharge and prevents arc over Grid Stabil...

Page 25: ...arge extra liquid on the drum surface is reduc ed for proper image transfer At the same time the toner image on the drum will be stabilized kVDC Toner Applied voltage 6 4 6 Transfer Transfer corona Radiates positive ions against the back side of the copying paper and these ions attract the negative toner particles onto the copying paper Paper 1 Transfer Corona Fixing Heat Dispersion Plate Heating ...

Page 26: ... 2 3 6 DEVELOPER ASSEMBLY 2 3 7 DRUM CLEANER ASSEMBLY 2 3 8 CASSETTE AND CASSETTE HOLDER ASSEMBLIES 2 3 9 PAPER PICKUP ROLLER ASSEMBLY 2 3 10 COPY CONVEYING ASSEMBLY 2 3 1 I HEATER ASSEMBLY 2 3 12 BLOWERS AND FANS 2 3 13 COPY SELECTOR SUBASSEMBLY 2 3 I4 SAFETY ASSEMBLY 2 3 15 COPYBOARD DRIVING MECHANISM ASSEMBLY 2 3 16 PEDESTAL ASSEMBLY 2 4 OUTLINE OF THE DRIVE SYSTEM 2 5 OUTLINE OF ORIGINAL MOVEM...

Page 27: ...ontrol Circuit see 3 4 9 3 4 10 Developer Assembly see 4 6 Air Input Blower Assembly see 4 14 Suction Blower Assembly see 4 14 Cassette Holder Assembly see 4 8 Safety Assembly see 4 16 Premix Valve Subassembly Toner Valve Subassembly see 4 6 Exposure Mask Subassembly see 4 3 Optical Assembly see 4 3 Copy Selector Subassembly see 4 15 Control Panel Assembly Microswitch Mounting Assembly Heater Asse...

Page 28: ...2 1 Fig 2 1 Breakdown of the NP 70 Second Printing June 1974 ...

Page 29: ...r duct Paper guide bracket Separation roller Skirt blade Cleaner blade Positive corona Original illumination lamp Light reflecting mirror Cassette holder frame Paper pickup roller 16 17 18 19 20 21 22 23 24 25 27 28 29 Paper feed guide plate Timing roller Paper feed guide plate Transfer corona Negative corona Drum cylinder Developer tray Developer reservoir A C corona Overall exposure lamp Main mo...

Page 30: ...Fig 2 2 NP 70 Parts Nomenclature Second Printing June 1974 ...

Page 31: ... image and drum move in synchronization The assembly consists of a chamber contain ing a minror and a lens unit Lens 180 mm F 4 5 In mirror type Magnification 1 1 Maximum size of original 297 mm x 420 mm JIS A3 The tone of a copied image is adjusted by turning the exposure dial located on the control panel which changes the size of the lens diaphragm The dial graduations are related to the lens F ...

Page 32: ... upward so that the rotating drum receives a constant coating of developer The proper development of the latent image is ensured by the inclusion of the developing tray the tray acts as a development electrode The developer contained in the assembly consists of a colloidal suspension of toner and liquid dispersant the latter acting as the carrier The charges assumed by these two elements are as fo...

Page 33: ...3 11 HEATER ASSEMBLY This assembly mounted within the Copy Conveying Assembly is used to heat the paper slight ly for the purpose of evaporating the dispersant absorbed during transfer As toner will smear with the presence of dispersant this evaporation step is necessary to permit handling of copies The toner will not smear however when the copy paper is dry therefore this step is known as Fixing ...

Page 34: ...e copyboard backward and forward as copying is performed 2 3 16 PEDESTAL ASSEMBLY This assembly is dual functional it can be used for storage only or used to mount a line con version transformer when the copier input A C voltage requirements differ from available voltages Second Printing lune 1974 CANON INC ...

Page 35: ...d with the revolution of the main motor to ensure that copies are made with the image position the same as that on the original Main Motor copyboard Reciprocation Drive Rotation of Drum Paper Pickup Drive Paper Conveying Drive Movement of Original Fig 2 3 General Diagram of the Drive System Movement of Copy Paper The following two figures show the elements of the drive system in two ways a block d...

Page 36: ...rocket 29 Driving Pulley 17 Pickup Roller Drive 30 Forward Sprocket Shaft 31 Return Sprocket 18 Clutch Gear A 32 Forward Clutch 19 Timing Roller Control 33 Return Clutch Clutch 34 Return Clutch Sprocket 20 Timing Roller 35 Forward Clutch Sprocket 21 Drive Chain B 36 Main Motor 22 Intermediary Shaft 37 Copyboard Wire 23 Intermediary Sprocket B 38 Drum Gear 24 Intermediary Sprocket A 39 Paper Pickup...

Page 37: ... Intermediary Gear i Drum Gear Separation Gear I V Separation Roller Separation Belt Separation Pulley r Paper Feed Gear f Pickup Roller Drive Shaft Clutch Gear B Roller Sprocket Pickup Cam l j Pickup Roller up down dnve Ladder Chain Shaft Sprocket Pickup Roller Sensitive Drum Separation Sprocket Ladder Chain Delivery Sprocket 2 Delivery Roller 2 Delivery Sprocket 1 Delivery Roller 1 Fig 2 5 Block...

Page 38: ...opyboard starts moving from right to left synchronized with the drum This is called the Exposure Process because the original is illuminated at this time 2 After exposure of the original the copyboard reverses its motion to the starting position where it waits for the start of the next exposure The movement of the copyboard during exposure affects the copy image directly so it is important that th...

Page 39: ...ately 400 sheets The inner plate of the paper cassette is pressed upward by two coil springs to ensure that the sheets in the cassette are constantly in contact with the separation claws 2 When the copying operation stazts the revolving pickup roller comes down contacts the top most sheet and advances it to the timing roller 3 As the timing roller operates to synchronize the paper feeding and the ...

Page 40: ... 2 8 Conveying Drive Mechanism Sepration Roller Idler Sprocket Delivery Sprocket 1 Chain Drive Sprocket 6 The visible toner image on the drum surface is transferred to the paper by the transfer corona and then the paper is separated from the drum and fed to the heater 7 The heater plate which is maintained at 180 C 5 C dries and fixes the toner image to the paper 8 The paper which has passed over ...

Page 41: ...ransfer Corona Separation Separation Roller Separation Belt Separation Subass y Fixing and Drying Heater r Delivery Roller 1 Copy Paper Guide l Delivery Roller 2 i Copy Tray AC Eliminator Fig 2 9 Diagram of Copy Paper Movement Residual Charge Elimination CANON iNC Second Printing lune 1974 ...

Page 42: ...ERVAL 3 3 5 PRESTART TIME 3 3 6 COPYING CYCLE 3 3 7 SECOND FEED INTERVAL 3 3 8 NEUTRAL TIME 3 3 9 STANDBY 3 4 OUTLINE OF ELECTRICAL COMPONENTS AND CIRCUITS 3 4 1 SWITCHBLE TAPS FOR AC LINE VOLTAGE COMPENSATION 3 4 2 AC LINE VOLTAGE FILTER 3 4 3 RECTIFICATION CIRCUIT CARD 3 4 4 RAPID START ILLUMINATION CIRCUIT 3 4 5 HEATER WAIT CONTROL CIRCUIT 3 4 6 DEVELOPER MONITORING CIRCUITRY 3 4 7 DEVELOPER TE...

Page 43: ...Copyboard Start MS2A Microswitch Jam Detection SL7 Enable MS3A Microswitch Jam Detection Jam Ckt Enable NO MS4 Microswitch Drum Stop Position MSS Microswitch Copyboard Release Lock and Toner Replenishment MS6A Microswitch Breaks Motor High Voltage Transformer Overall Exposure Circuit due to Jam MS6B Microswitch Breaks Heater Circuit due to Jam MS7 Microswitch Copy Start by pushing Copy Button MS8 ...

Page 44: ...te Insertion MSD1 Microswitch Door Switch Interlock MSD2 Microswitch Door Switch Interlock 4 NFB1 Circuit breaker Protection of AC Line NFB2 Circuit breaker Protection of Main Motor High Voltage Transformer and Overall Exposure Lamp NFB3 Circuit breaker Protection of 24VDC Power Supply Circuit NFB4 Circuit breaker Protection of SVDC Power Supply Circuit 5 LVT Low Voltage Transformer Develops 24VDC...

Page 45: ... Temperature sensitive Fuse Prevention of Excessive Temperature Rise inside the Heater Assembly melts at 150 C 9 I 1 FL1 Fluorescent Lamp Overall Exposure 1OW FL2 3 Fluorescent Lamp Original Exposure 25W 12 PL2 Pilot Lamp Neon Lamp Paper Jam Indication Line AC voltage PLS Pilot Lamp Neon Lamp ON OFF Indication line AC voltage 13 PL1 Pilot Lamp Tungsten Lamp Ready Indication 24VDC PL3 Pilot Lamp Tu...

Page 46: ...Prolongs Warm up when body temperature is below 15 C 16 M1 Motor Drum Copy Conveying Ass y Copyboard and Pick up Unit Drive 1 17 M2 MZ Motor Developer Mixing and Feeding 18 _ r FM1 Fan Motor Paper Separation and Paper Feed FM2 Fan Motor Suction and Exhaust FM3 Fan Motor Air Input and Operation 19 cr C 1 Electromagnetic Clutch Forward Copyboard Drive C 2 Electromagnetic Clutch Reverse Copyboard Dri...

Page 47: ...eloper Density SL7 DC Solenoid Breaks when jam occurs M1 FM Heater and High Voltage Power Circuit releasing MS6A and MS6B 21 I CNT1 Counter Counts Half size Copies reproduced CNT CNT2 Counter Counts Full size Copies reproduced CNT3 Counter Counts Total Copies reproduced Key Counter 22 K1 Relay Initiates Copy Operation K 1 3 1 K2 Relay Initiates Forward Copyboard Movement K3 Relay Initiates Reverse...

Page 48: ...eration r K301 Relay Controls Developer Temperature 23 NC NO 1 KI 1 KI 1 K1 2 K2 1 etc Point of Relay Contact Designates the number of the Relay Contact pair NC and NO indicate Normally Closed or Normally Open 24 Positive Corona Assembly 6 4kVDC Radiation to drum Negative Corona Assembly 6 4kVDC Radiation to drum AC AC Corona Assembly 7kVAC Radiation to drum Transfer Transfer Corona Assembly 6 OkV...

Page 49: ...Device 28 Q Silicon Control Rectifier Switching 29 Q Transistor Switching and Amplification 30 o Q IC Operational Amplifier Differential Amplification of minute signals 31 Q Programmable Unijunc tion Transistor Switching 32 D Silicon Varistor Protection of Electronic Components 33 CdS Photoconductive Cell Sensing of Light for operation initiating 34 R Fixed Resistor 35 J V VR Variable Resistor Per...

Page 50: ...citor 38 FLT Low pass Filter Elimination of Noise on AC input voltage line 230 VAC line voltage only wry i r 39 L L Inductor 40 TH Thermistor Rotary Switch Sensing of Temperature Changes Table 3 1 Electric Components Second Printing June 1974 CANON INC ...

Page 51: ...conduction i e transistor UJT energization i e relay solenoid etc b OFF inidicates anon operational condition and is opposite of ON c HI indicates either the high level state of the comparitor inputs outputs or an above normal condition of temperature d LO indicates aloes level state opposite to HI e ENABLED indicates that the element denoted operates only through some indirect means i e heater op...

Page 52: ... This decreases the friction between the drum and cleaner blade and prevents the drum surface from being damaged c Motor M2 comes ON immediately to stir the developer liquid in the Developer Assembly This stirring is performed to ensure uniform density of the liquid before copying is performed SW ON Capacitor C16 completes its charging and turns on the illumination lamps FL2 3 so that they will st...

Page 53: ...t opening of the conduction path between K7 and Q22 will result in the turning OFF of Q22 and thus the deenergization of K7 STEP SS The delay hold path for relay K7 is opened resulting in deenergization of the relay The drum will continue to turn however until the alternate path for voltage to main motor M1 through MS4 is opened STEP 6S The alternate path for voltage to M1 is broken at this time a...

Page 54: ...ette 3 The cassette is properly seated 4 Developer is in the Developer As sembly and the assembly is full 5 There is no jam condition in the copier 6 All doors are closed and circuit breakers are reset 7 Timing of the drum is based on normal conditions as depicted in the timing chart 8 All components are operating at correct levels 9 The machine is otherwise in cor rect working order CANON INC ...

Page 55: ... Q15 ON Q16 ON C30 STARTS CHARGING Q20 ON Q45 ON K7 ON FL1 ON FM1 ON FM3 ENABLED See 3 4 7 HVDC ON D C CORONAS ON HVAC ON LA C CORONAS ON M1 ON LDRUM STARTS TURNING STEP 3S DRUM 296 7 3 0 rev TIME 17 0 secs C30 CHARGING COMPLETED Q43 ON Q44 OFF C16 STARTS DISCHARGING Q45 OFF Q21 BIAS ON Fig 3 1 START Flowchart Sheet 1 of 1J STEP 3S DRUM 296 7 TIME 17 0 secs C30 CHARGING COMPLETED Q43 ON Q44 OFF C1...

Page 56: ...ze and full size copy paper The initial steps of the flowchart suffixed with the letter C are steps common to both paper sizes However beginning with STEP 5 the steps are suffixed with either CH COPY half size or CF COPY full size The following table 3 3 gives a brief explanation of the actions occurring at each block of the COPY flowchart It is recommended that the COPY flowchart be followed when...

Page 57: ... ON in prepa ration for the forward movement of the copyboard SL6 is also enabled for toner feeding if density is low reference the ATR ckt flowchart STEP 3C As MS1A is actuated the copyboard forward drive clutch C 1 moves the copy board forward for the start of the first copy cycle After this step flow pro ceeds to either Half size or Full size operation STEP 4C If the copy being made is the last...

Page 58: ...ge in the jam detection ckt STEP 12CH STEP 13CH Capacitor C25 finishes the discharging action begun in STEP 9CH and causes K10 to deenergize Should this be the last copy K11 is now set to be turned OFF when the next MS3A pulse occurs However if further copying is being performed K10 will again be energized to ensure K11 is held ON for jam de tection both In this step the copyboard motion stops as ...

Page 59: ...dition as in STEP IOCH As the copyboard is no longer moving K10 has remained deenergized since STEP 19CH STEP 13CH Thus the MS3A pulse acts to turn K11 OFF The jam detection circuit is now deactivated in preparation for the STANDBY condition Although the drum position and time are different this step is the same as STEP 20CH STEP SS that is completion of the feed interval as capacitor C16 com plet...

Page 60: ...This is similar to STEP SCF STEP 12CH but will occur every copy cycle rather than once in a copy ope ration series as was the case in half size copying Capacitor C25 finishes the discharging action in STEP 7CF and causes K10 STEP 9CF to deenergize K11 is now set to be turned OFF when the next MS3A pulse occurs This is similar to STEP 13CH The copyboard advances across MS9 and signals a change of c...

Page 61: ...e are different this step is the same as STEP 17CF STEP 20CH that is completion of the feed interval as capacitor C16 com last only pletes its discharging STEP 17CF The copyboard is released so that the next copy cycle can begin as the drum reaches 0 This is the same as STEP 3C repeat only STEP 18CF The delay hold path for relay K7 is broken at this time as in STEP 6S last only The second or later...

Page 62: ...ette 3 The cassette is properly seated 4 Developer is in the Developer As sembly and the assembly is full 5 There is no jam condition in the copier 6 All doors are closed and circuit breakers are reset 7 Timing of the drum is based on normal conditions as depicted in the timing chart 8 All components are operating at correct levels 9 The machine is otherwise in cor rect working order CANON INC ...

Page 63: ... STEP SCH DRUM 40 0 1 3 rev TIME S 4 secs COPY SELECTOR RELEASES LMS7 OFF DRUM 50 0 1 3 rev TIME 5 46 secs MS2A ON SL ENABLED DRUM 77 7 1 4 rev TIME 5 77 secs MS14 ON SLS OFF SL4 ON LCOPY PAPER STARTS PICKUP CNT3 ON CNT1 ON Q I 3 0 ON 131 ON C2S CHARGES Q32 ON K10 ON Fig 3 2 COP Flowchart Sheet 1 of 3J STEP 8CH DRUM 109 5 1 S rev TIME 6 12 secs MS2A OFF SL7 DISENABLED STEP 9CH DRUM 132 0 1 S rev T...

Page 64: ...ette 3 The cassette is properly seated 4 Developer is in the Developer As sembly and the assembly is full 5 There is no jam condition in the copier 6 All doors are closed and circuit breakers are reset 7 Timing of the drum is based on normal conditions as depicted in the timing chart 8 All components are operating at correct levels 9 The machine is otherwise in cor rect working order CANON INC ...

Page 65: ...STARTS CHARGING O STEP 18CH DRUM 180 2 67 rev TIME 10 9 secs APPROX COPY PAPER STOPS BLOCKING CdS3 Q25 O6 HI Q29 GATE ON Q26 ON C20 DISCHARGES STEP 19CH DRUM 194 8 2 7 rev TIME 11 07 secs MS3A ON Q33 ON Q34 OFF K11 OFF STEP 20CH DRUM 324 6 4 1 rev TIME 16 51 secs C1 6 DISCHARGING COMPLETED Q17 OFF K6 OFF FL2 3 WARMING Q 18 OFF Q19 ON Q20 OFF Q21 OFF STEP 21CH DRUM 0 0 4 2 rev TIME 16 9 secs MSlA O...

Page 66: ...ette 3 The cassette is properly seated 4 Developer is in the Developer As sembly and the assembly is full 5 There is no jam condition in the copier 6 All doors are closed and circuit breakers are reset 7 Timing of the drum is based on normal conditions as depicted in the timing chart 8 All components are operating at correct levels 9 The machine is otherwise in cor rect working order CANON INC ...

Page 67: ...26 ON L C20 DISCHARGES STEP 17CF DRUM 235 4 4 8 rev TIME 19 52 secs C16 DISCHARGING COMPLETED Q17 OFF K6 OFF LFLz 3 WARMING Q18 OFF Q19 ON LQ20 OFF Q21 OFF Fig 3 2 COPY Flowchart Sheet 3 of 3J STEP 15CF STEP 16CF DRUM 235 4 2 8 rev TIME 11 52 secs MS8 ON K3 OFF C22 OFF L COPYBOARD STOPS AT 249 7 K1 ON C16 HOLD THRU D16 DRUM 330 3 09 rev TIME 12 57 secs APPROX COPY PAPER STOPS BLOCKING CdS3 L Q25 H...

Page 68: ...ponse to stop copier operations will occur at 410 of drum rotation 4 55 seconds of operation from the start of the copying cycle during which the jam occurs 2 EXIT JAM An exit jam indicates that the copy paper has begun but has failed to complete its exit of the copier In this type of jam the paper is usually free of the drum area but is in conti nuous contact with the heater Because the heater te...

Page 69: ...last copying cycle is completed STEP 1J The release of MS14 as the copyboard continues its advance results in the start of capacitor C25 discharging STEP 2J The first actuation of MS3A after MS14 causes the Jam Detection Circuit to turn on due to the energizing of relay K11 for the purpose of detecting a Delay jam occurring in the present copying cycle NOTE In the case of half size operation K11 t...

Page 70: ...n exiting at its normal time see STEP SJD STEP 6JD the copier is turned off with the actuation of MS2A about 20 of drum revolu tion later Solenoid SL7 energizes due to the fact that Q29 K11 and MS2A are all simul taneously ON As in the case of Exit jam microswitches MS6A MS6B are released to deacti vate the copier to prevent drum rotation and heater operation which would result in damage to the co...

Page 71: ...ette 3 The cassette is properly seated 4 Developer is in the Developer As sembly and the assembly is full 5 There is no jam condition in the copier 6 All doors are closed and circuit breakers are reset 7 Timing of the drum is based on normal conditions as depicted in the timing chart 8 All components are operating at correct levels 9 The machine is otherwise in cor rect working order CANON INC ...

Page 72: ...200 56 rev TIME CYCLE START PLUS 2 22 secs 1 DRUM CYCLE START PLUS 410 1 14 rev STEP 6JD TIME CYCLE START PLUS 4 55 secs CYPY PAPER IN EXIT FOR 10 0 secs C20 CHARGING COMPLETED I Q27 ON Q28 ON Q39 ON ESL ON ACTUATOR TRIP LEVER RELEASED MS6B OFF HEATERS DISENABLED MS6A OFF M1 OFF DRUM STOPS TURNING HVAC OFF AC CORONAS OFF HVDC OFF DC CORONAS OFF FL1 OFF REMOVE JAM C25 DISCHARGING COMPLETED Q32 OFF ...

Page 73: ...erning this time refer to the section on the Heater Wait Control Circuit in 45 3 3 2 WARM UP TIME Due to the design of the Timer Circuit it is impossible to begin copy operations with the turn ing ON of the main power switch This restriction is a built in safety measure to allow the copier a period in which it can prepare itself for copying The designation for the interval in which copy is impossi...

Page 74: ...irst feed interval Prestart Time is designated as the interval from the depressing of the COPY button to the start of copying operations The dur ation of this time is 4 9 seconds and is determined by the charge time of C13 0 2 seconds and 1 17 revolutions of the drum This time will be constant in either half size or full size cop copy cycles see flowchart C NI to 3 3 6 COPYING CYCLE STEP 4C The po...

Page 75: ... the drum is designated Neutral Time Due to slight differences in operation timing the duration of neutral time will vary according to the type of operation previously performed This timing is as follows 1 When the initial starting operations are performed and the COPY button is not pressed the time will be the last 4 0 seconds This period is shown in the START flowchart as STEP 7S time 25 0 secon...

Page 76: ...for any fumes which might build up within the copier body due to developer evaporation 4 The illumination lamps FL2 3 are maintained at an energy level close to that needed for illumination This warming action ensures that the lamp illumination will stabilize rapidly during Prestart Time as the next copying operation is begun Second PrintingJune 1974 CANON INC ...

Page 77: ...TART TIME 4 9 SECS 20 2 SECS MINIMUM I E I COPYING CYCLE 3 6 SECS 4 9 SECS I 8 5 SECS I 2ND FEED INTERVAL 8 0 SECS I NEUTRAL TIME 3 7 SECS 16 5 SECS I I STANDBY 20 2 SECS I COPY OPERATION FULL SIZE 120 SECS 20 SECS 2 MINS I PRESTART TIME 4 9 SECS 0 0 SECS I 4 9 SECS STANDBY f I I 24 2 SECS MINIMUM COPYING CYCLE 6 6 SECS 1 1 5 SECS I 2ND FEED INTERVAL 8 0 SECS I I I 19 5 SECS NEUTRAL TIME 4 7 SECS ...

Page 78: ...tic Diagram 3 4 3 RECTIFICATION CIRCUIT CARD ALL COPIERS O LINE AC The conversion of the AC voltage stepped down by the low voltage transformer LVT is performed by the rectification circuit card Part of this card includes the DC voltage regu lator for which the following explanation is provided 1 VOLTAGE REGULATOR TYPICAL If the output of the voltage rectifier is used as a direct power source it w...

Page 79: ...lied to the base of Q2 increases Conversely the current flow through Q2 Q1 increases and output voltage Eo increases to its original level e If the output voltage increases the previous operation is reversed resulting in a reduction back to the correct output voltage level The output voltage can be varied as desired by using potentiometer VR1 NOTE Due to large current flow two transistors have bee...

Page 80: ...heat them and release low energy level free electrons b From the primary side an output is provided to apply 240VAC to the electromagnetic field radiator As the radiator is parallel to and in close proximity with the lamps its electromagnetic field increases the energy level of the free electrons formed by fillament warming c The start of a copy operation causes relay K6 to energize and thus apply...

Page 81: ...cuit is explained in the flowchart Fig 3 10 and table 3 5 accompanying r TH2 l ovDc o PL1 COMP K14 K14 Q47 R134 NETWORK AMP CON CON K14 iCHMITT CKT Q49 I I I I HEATER WAIT CON CKT CARD I J PART OF TIME CKT CARD K7 Q19 Q20 Q16 o 24VDC O OVDC I I Fig 3 9 Heater Wait Control Circuit Associated Components Second Printing lune 1974 CANON INC ...

Page 82: ...31 has just begun charging STEP 1HW The charge of capacitor C31 reaches 4VDC and the Schmitt trigger is activated to turn ON Q49 and thus PL1 As this occurs C31 begins to discharge STEP 2HW Capacitor C31 discharges sufficiently to deactivate the trigger circuit PL1 As STEP 3HV II this occurs charging is resumed until STEP 2HW can be repeated As the temperature of the heater reaches 160 C relay K14...

Page 83: ...ette 3 The cassette is properly seated 4 Developer is in the Developer As sembly and the assembly is full 5 There is no jam condition in the copier 6 All doors are closed and circuit breakers are reset 7 Timing of the drum is based on normal conditions as depicted in the timing chart 8 All components are operating at correct levels 9 The machine is otherwise in cor rect working order CANON INC ...

Page 84: ...Q49 OFF PLl OFF 1 C END C31 CHARGED TO 4VDC I Q48 ON C31 STARTS DISCHARGING Q49 ON PLl ON C31 DISCHARGING COMPLETED I Q48 OFF C31 STARTS CHARGING Q49 OFF PLI OFF T I H2 RESISTANCE LO y Q46 O2 HI Q46 O6 LO LQa7 ON K14 ON Q48 OPERATION VOLTAGE REMOVED Q48 DISENABLED PLl CONDUCTION BATH OPENED PLl DISENABLED Fig 3 10 Heater Wait Flowchart Second Printing June 1974 ...

Page 85: ...T AMP Q14 L2 O SVDC A T R CIRCUIT CARD PL3 MS12 J Fig 3 11 Developer Monitoring Circuitry O OVDC 1 OPERATION A T R CIRCUIT The A T R circuit which constantly monitors the density of the developer liquid operates as shown in the flowchart in Fig 3 12 When the density drops below the correct level due to copy operations the illumination of photocell CdS1 is sufficient to cause the comparator output ...

Page 86: ... copier the level of the developer in the Developer Assembly is con stantly monitored Should the level fall below the prescribed safety limit 1 8 the actions shown in the flowchart in Fig 3 13 will occur STEP 1DL REFILL DEV DEVELOPER LEVEL LO DEVELOPER ASS Y FLOAT DROPS LMS12 ACTUATOR RELEASED MS12 ON PL3 ON K9 ON Kl ACTIVATION PATH OPENED K1 FAILS TO ENERGIZE FOR NEXT COPY CYCLE COPIER GOES TO ST...

Page 87: ...nity of the Developer Assembly to 42 3 C through the turning ON of FM3 This action prevents the excessive evaporation of the dispersant carrier of the developer fluid which occurs at high copier body temperatures Fig 3 14 shows the developer temperature control circuit and its associated components LINE AC p 24VDC p 5VDC p OVDC O LINE AC p r DEVELOPER TEMP CON CKT CARD i VOLT DIVID L _ TH3 CURRENT...

Page 88: ... in Fig 3 15 STEP 1DT COPIER TEMPERATURE HI TH3 RESISTANCE LO Q301 ON Q302 OFF Q303 OFF K30I OFF FM3 ACTIVATION PATH CLOSED Fig 3 IS Developer Cooling Flowchart FM3 ON NO EFFECT UNTIL NEXT COPY CYCLE As shown in the flowchart operation of FM3 is the result of the circuit action which de energizes relay K301 to close the activation path for cooling fan FM3 Second Printing lune 1974 CANON INC ...

Page 89: ... is properly seated in the copier This additional portion of the jam detection circuit is depicted in Fig 3 16 with its associated components 24VDC O PART OF JAM DET CKT CARD CdS2 COMP NETWORK AMP K9 Q24 _ PL4 L3 SVDC 1 MS15 Fig 3 16 Paper Cassette Monitoring Circuitry O OVDC 1 OPERATION CASSETTE EMPTY This circuitry operates to bring the copier to STANDBY whenever the cassette becomes empty This ...

Page 90: ...EXT COPY CYCLE COPIER GOES TO STANDBY REFILL PAPER Fig 3 17 Cassette Empty Flowchart As shown in the flowchart the copier returns to STANDBY as result of the opening of the path for activating relay K1 for the next copy cycle If this action were not performed the copier would sense a Delay jam and respond accordingly Second Printing une 1974 CANON INC ...

Page 91: ...15 ACTUATOR RELEASED I MS15 ON r PL4 ON Ili K9 ON Kl ACTIVATION PATH OPENED Kl FAILS TO ENERGIZE FOR NEXT COPY CYCLE COPIER GOES TO STANDBY RESEAT UNIT Fig 3 18 Cassette Not Seated Flowchart The copier is prevented from operating when the cassette is not seated in the same manner as when the cassette is empty the K1 activation path is broken to ensure that operation of the copier cannot be accompl...

Page 92: ...erature range assures the proper fixing action as the copy exits the machine Fig 3 19 shows the heater control circuit and its associated components 100VAC p 24VDC OVDCO 100VACO TH1 r COMP NETWORK AMP C28 Q41 TP MS6B H3 T H2 Q42 H1 HEATER CONTROL CIRCUIT CARD L J Fig 3 19 Heater Control Circuit Associated Components The operation of the heater control circuit is explained in the flowchart in Fig 3...

Page 93: ... pulse is immediately felt in the secondary winding of the transformer and results in the turning ON of triac Q42 for 1 2 alternation of the input A C voltage It should be noted that the discharge time of C28 is almost instantaneous and thus Q41 is only ON for a short period As soon as Q41 turns OFF C28 begins charg ing again to resume the pulse generation cycle STEP 2H0 As soon as the heater temp...

Page 94: ...ette 3 The cassette is properly seated 4 Developer is in the Developer As sembly and the assembly is full 5 There is no jam condition in the copier 6 All doors are closed and circuit breakers are reset 7 Timing of the drum is based on normal conditions as depicted in the timing chart 8 All components are operating at correct levels 9 The machine is otherwise in cor rect working order CANON INC ...

Page 95: ...GES THRU Q41 TP PULSE GENERATED Q42 ON HEATERS ON FOR 1 2 CYCLE OF AC VOLTAGE Q41 OFF C28 STARTS CHARGING STEP 3H0 HEATER TEMPERATURE HI THI RESISTANCE LO Q40 2 HI Q40 6 LO C28 FAILS TO CHARGE TO Q41 GATE VOLTAGE Q41 GATE OFF Q41 OFF TP NO PULSE GENERATED Q42 OFF HEATERS OFF TILL HEATER TEMPERATURE LO C END Fig 3 20 Heater Operation Flowchart Second Printing June 1974 ...

Page 96: ...er and one for activating the heaters at a high level when the temperature drops c The Zero Cross circuit uses astep down transformer to convert the high A C line voltage for controlling operations of the circuit Fig 3 21 shows the Zero Cross circuit and its associated components TH1 OVDCp COMP NET P FULL WAVE 1 ZERO CROSS P 0 TP231 E T 1 4 ZERO CROSS HALF WAVE D231 T201 P 0 TP231 _ LINE A O C I M...

Page 97: ...with triggering for low level operation as follows reference Fig 3 22 3 23 a The voltage from rectifier D231 is applied to the base of Q233 and results in the alternate ON OFF action of the transistor R238 R24 C233 R D235 VR231 Q233 C234 R237 Q234 3 TP231 Fig 3 22 1 4 Zero Cross Circuit b During the periods that Q233 is conducting the charge of capacitor C234 remains on stant However during period...

Page 98: ... Voltage TP231 3N4 Voltage Heater Voltage Fig 3 23 depicts the waveforms for the operation of the 1 4 zero cross circuit Bias voltage of Q233 I I I OFF I I I E Charging I Charging I I I I I i i i s I Fig 3 23 1 4 Zero Cross Waveforms Second Printing June 1974 ...

Page 99: ...e of Q231 which doubles the conduction periods when compazed to Q233 and the lack of resistance in the chazge path of C232 which shortens the charge time when compazed to C234 one spike is developed in TP231 for each half cycle of AC voltage Fig 3 24 1 1 Zero Cross Circuit d The frequency of the triggers developed by the 1 1 zero cross circuit is thus four times the rate of those developed by the ...

Page 100: ...e operation of the 1 4 zero cross circuit Bias voltage of Q231 I I l i I I I j I I I I I I I I I I i i I I I I I I I I I pN OFF I I I I l I I i I Ir I I i I I I I I I I i I I I I I I I I I I I I I i I I I I I I I I I 1 I I I 3 i I I I I I j I 5 i I I I I I I I I I I 2 4 Fig 3 25 1 1 Zero Cross Waveforms CANON INC Second Printing June 1974 ...

Page 101: ...ea enclosed by the dotted line representing the voltage converter LINE VOLTAGE INPUT SW J CONVERTER TRANSFORMER METER o COPIER AC o OUTPUT J _ PEDESTAL Fig 3 26 Voltage Adapter Pedestal Schematic Diagram It should be noted that two converters are available for use with the pedestal Table 3 provides the specifications for these two models Converter Model Adaptable Input Voltage Input Taps Output Vo...

Page 102: ...ASSEMBLY 4 7 DRUM CLEANER ASSEMBLY 4 8 CASSETTE HOLDER ASSEMBLY 4 9 PAPER CASSETTE ASSEMBLY 4 10 PAPER PICKUP ROLLER ASSEMBLY CONTROLLER ASSEMBLY 4 11 COPY CONVEYING ASSEMBLY 4 12 PAPER SEPARATING SUBASSEMBLY 4 13 HEATER ASSEMBLY 4 14 BLOWER AND FAN ASSEMBLIES 4 15 COPY SELECTOR SUBASSEMBLY 4 16 SAFETY ASSEMBLY 4 17 COPYBOARD DRIVING MECHANISM ASSEMBLY ...

Page 103: ...orward direc tion synchronized with the movement of the drum and the feeding of paper It is particular ly important that bounce or other erratic movements be minimized during the exposure por tion of the copyboard travel 4 1 2 ASSEMBLY MAIN COMPONENTS copyboard Cover Subassembly Convenience Cover Rear Glide Rail Glass Retainer Roller Unit Front Glide Rail Fig 4 1 copyboard Assembly Main Components...

Page 104: ...iginal Along its edges are found reference points for positioning originals of various sizes 3 CONVENIENCE COVER The convenience cover is a specially shaped tray like piece ideally suited for use when copying pages from book or other bulky objects 4 FRONT GLIDE RAIL This component acts as an assembly frame member as well as a rail member for copyboard movement copyboard Locking Cam Front Glide Rai...

Page 105: ...this rail The rear rail components are shown in Fig 4 3 copyboard Wire Rear Glide Rail copyboard Stop Cam Fig 4 3 Rear Rail Components copyboard Reversing Cam Paper Feed Cam 6 ROLLER UNITS There are sixteen 16 roller units used for the two glide rails As there are some differences in the roller units used care must the taken to position the rollers correctly Fig 4 4 shows the roller units correctl...

Page 106: ...er Unit Positioning Rollers It should be noted the eight 8 central roller units marked in Fig 4 4 are only roller re tainers Also the units with rollers have their felt padded end alligned toward either the right or left end of the rail in which they are mounted Second Printing June 1974 CANON INC ...

Page 107: ...r at the copier left end of the rail be removed and that the copyboard be removed from the right end of the copier body d It is preferrable to remove the copyboard without removing the tap in pins on the main body rails as they are easily lost if removed e When removing the assembly from the copier right end it is necessary to remove the stopper screws and the copyboard wire from the left end of t...

Page 108: ...is time placing the wire in the outer groove as shown in Fig 4 7 Note that the wires cross Outer Groove Fig 4 7 Copyboard Wire Installation CJ d Secure the wire to the operator right end of the copyboard and seat the inner section of wire in the groove of the idler pulley see Fig 4 8 Fig 4 8 Copyboard Wire Installation DJ In performing the above procedure it is possible to seat the wire in the idl...

Page 109: ...rd wire at a point midway between the wire pulley and the idler pulley as shown in Fig 4 9 200g Idler Pulley Wire Pulley Fig 4 9 Measuring of Wire Tension c Pull on the balance until the wire is deflected 3 4 mm from its normal position With this amount of wire deflection the balance should indicate 200 grams d If the wire tension is not correct adjust the tension of the idler pulley by sliding th...

Page 110: ...screws to permit movement of the cam c Slide the cam as follows for proper regulation Paper Condition Cam Adjustment Paper is fed early resulting in a white area at the copy leading edge Move the cam in the direction of Paper is fed late resulting in an image overlapping the copy leading edge Move the cam in the direction of Paper Feed Cam Copier Left Cam Mounting Screws Copier Right Fig 4 12 Pape...

Page 111: ...C is applied to the filaments of the fluorescent lamps This voltage heats the filaments and releases low energy level free electrons b The electromagnetic field radiator to which 240VAC is continuously applied generates an electromagnetic field which additionally excites these electrons c When copying begins full AC voltage is applied to the filaments ionization takes place immediately to illumina...

Page 112: ...ass as indicated in Fig 4 14 Light Reflector Slit Fig 4 14 Lamp Illumination Pattern Illumination I Lamp I I I I 2 ELECTROMAGNETIC FIELD RADIATOR The electromagnetic field radiator is a plate shaped in a semi wrap around fashion to ensure contact with the lamp surfaces 240VAC is continuously applied to this radiator to assist in the excitation of the lamps As such the field radiator must be comple...

Page 113: ...s are changed as follows a Unscrew the Front Right Door retaining screw and open the door b Disconnect the assembly connector J21 and draw out the assembly squarely on the rail being careful not to allow the lamps or any other part of the assembly to rub against the control panel c Separate the lamp from the front socket by drawing the socket in the direction indicated by the arrow in Fig 4 16 Ill...

Page 114: ...ary a If dust or lint is present wipe the components with dry lintless cleaning paper b If they are smeared with toner or fingerprints wipe first with alcohol dampened cleaning paper and then with dry lintless paper NOTE Always wear gloves when replacing the fluorescent lamps to prevent soiling If fingerprints or other marks mar the surfaces of the lamps wipe them care fully before installing See ...

Page 115: ... to form a complete image no interferance should be present along the path of light travel Dustproofing glasses 1 2 and the reflecting mirror should be kept clean to preserve high quality copying The optical chamber interior is protected from contamination by a dustproofing cover The diaphragm in the lens unit controls the light intensity to the drum surface depending on the sheet original contras...

Page 116: ... They protect the minor and the lens inside the chamber from dirt by sealing up the chamber As an image passes through these glass plates they must be completely clear and flawless to pass the image correctly 2 IMAGE MIRROR This minor must reflect the image accurately to the lens unit thus the reflection angle and the plane angle are very critical 3 DUSTPROOFING COVER The light chamber is covered ...

Page 117: ...F9 1 1 more than 10 lines mm 6 EXPOSURE ADJUST LINE This line is made of polypropylene with a diameter of 0 4 mm Its length is 118 cm when tied to the hooks of its tension spring and connects the exposure dial to the diaphragm mechanism of the lens unit These control the light intensity to the photosensitive surface of the drum unit 4 3 3 REMOVAL INSTALLATION ACTIONS The Optical Assembly and Lens ...

Page 118: ...Step 3 Pass the end through the first loop from below Step 4 Pass the end over the line and through the second loop from above to below and pull on it to tighten the knot slightly Step 5 Place the hook of the spring in the first loop and pull on the line to tighten the line securely to the hook Step 6 Measure 118 cm from the hook and mark it on the line 118 Step 7 Repeat steps 1 5 for the second k...

Page 119: ...cm see Fig 4 20 Fig 4 20 Adjust Line Replacement AJ c While holding the tension spring line securely in position pass the line in the side groove of the dial pulley and wrap it under the stud and back in the groove see Fig 4 20 d Then wrap the line around the dial pulley one time and pass it under the idler pulley in the inner groove see Fig 4 21 Fig 4 21 Adjust Line Replacement BJ CANON INC Secon...

Page 120: ...e Adjust ng max ccw g Check whether the apeture adjust ring is at its most extreme ccw position when the ex posure dial is set at 9 If not it is easily adjusted by loosening the three retaining screws on the side of the dial pulley and then turning the aperture adjust ring ccw until the ex posure dial is at 9 The complete installation is seen in Fig 423 Retaining Screws Dial Pulley Exposure Adjust...

Page 121: ...onal details concerning assembly cleaning 2 ADJUSTMENTS The adjustment of the aperture slit should be performed as follows See Fig 4 24 a If the drum sensitivity is F type drum photo receptor serial number ends with 0 or 7F Position the blade so that the width of the slit is 8 mm at the center and 12 5 mm at the ends 130 mm from the center of the exposure mask This position should be ap proximatel...

Page 122: ...The photosensitive drum and the drum gear are mounted on the same shaft Although the gear and drum are not bolted directly together they are held in fixed relationship to one another by a stud protruding from the gear This stud engages a notch in the rear drum flange when the gear and its attached components and the drum and its attached components are placed on the shaft together 4 4 2 ASSEMBLY M...

Page 123: ...the rear side of it All of the cams have a fixed position for mount ing on the Drum Gear and each has one specific function in relationship to the total operation of the NP 70 3 FRONT SIDE HOLDER PANEL MOUNTING PLATE This Front side Holder contains the spring which when installed presses the Drum Shaft to ward the copier rear for proper seating 4 SHAFT HOLDER REAR This Shaft Holder installed on th...

Page 124: ... out the complete drum carefully grasping the front side flange so that the drum s sur face is not scratched When removing the drum do not touch the surface f Repeat steps a e in reverse order for installation During installation make sure that the following points are observed g When the Drum Unit is placed in the copier make sure that the wrapping direction of the photosensitive sheet is opposit...

Page 125: ...e that the internal rib of the drum cylinder engages the notch provided for it in the flange edge see Fig 4 28 Flange front Notch Drum Cylinder Fig 4 28 Drum Unit Reassembly b Fit the other flange to the drum cylinder again engaging the drum rib with the flange notch c Secure the above assembled parts with the long flange retaining screws NOTICE PROCEDURES FOR REPLACEMENT OF THE DRUM CYLINDER Fit ...

Page 126: ...5 RESIDUAL CHARGE ELIMINATOR ASSEMBLY Neutralizes any remaining charge on the paper after the fixing process 4 5 2 ASSEMBLY MAIN COMPONENTS As the five coronas similar in function although individual in construction the following main components description are applicable to essentially all assemblies 1 RADIATING ELEMENT Each corona contains an element to which a high voltage is applied This high ...

Page 127: ...ring and serves as a means of securing the corona wire 5 GRID WIRE Included with the A C corona is a grid wire of similar properties to the corona wire radiating elements This grid positioned between the A C corona and the drum is essential to the LP process due to its stabilizing of the discharge process which occurs when the drum is ex posed to the image The potential of this grid is OV due to g...

Page 128: ... screw A and tighten the screw to secure the new wire c Pass the guide wire around and under the upper ridge lip of the eliminator housing place it in notch 2 and bring it diagonally across to notch 3 d Keeping the line taut bring it up notch 4 and take it diagonally across to the notch 5 e Repeat the same procedure across the face of the Eliminator Assembly However from notch 20 the line is wound...

Page 129: ... wire with the rear assembly terminal In the case of the A C Corona Assembly only one loop is connected Corona Wire Fig 4 32 Attaching Corona Wire d Position the other end of the wire not connected to the spring on its mounting stud in the front termination cover e Pass the wire s over the seating position s of the wire guides and secure the spring to the rear teminal using tweezers f Set the coro...

Page 130: ...pass it around the front D stud to the rear D stud i After going around the rear D stud pass the wire around the rear C stud j From the rear C stud feed the wire around the front C stud to the retaining screw 0 0 0 0 0 Rear Grid Hanger A C D E O O O O O Front Grid Hanger 0 0 0 0 0 B C D E O O O 0 0 0 0 lei C D E O O O ro o o 0 0 A O B C D E OOO O Retaining S rew a b c d e Fig 433 Wiring Procedure ...

Page 131: ...ark represents 0 1 mm vertical movement of the wire either up or down Turning the adjust screws counterclockwise increases the surface potential of the drum due to the corona wire moving closer to the drum On the other hand when turned clockwise the surface potential is decreased NOTE When making any adjustment always note the position of the screw Turn the screw slowly increasing in small increme...

Page 132: ... comes into contact with the surface of the drum The liquid comes through a hole in the bottom of the developing tray and flows to the ends of the tray due to a groove running from front to back This groove provides for complete coating of the drum The density of the developing liquid is kept constant electronically by a unit called the Auto matic Toner Replenishment ATR Subassembly Additionally t...

Page 133: ...LY MAIN COMPONENTS Squeezing Roller eveloping Tray Developing Tray Holder ATR Subassembly Reservoir Cover Developer Resevoir Fig 4 35 Developer Assembly Main Components Toner Bottle Holder CANON INC Second Printing June 1974 ...

Page 134: ...main components of this subassembly Upper Cover ATR Printed Circuit Board Density Detector Subassembly Housing Fig 4 36 ATR Subassembly Main Components The ATR Subassembly operation is divided into two areas mechanical and electronic In this section only the mechanical operation will be explained For information about the electronic operation refer to Chapter 3 of this manual Second Printing June ...

Page 135: ...nd the photocell resistance drops When the resistance drops too low activation of the ATR circuit occurs and toner is fed to the Developer Assembly see section 3 4 for explanation of circuit operation CdS Photoce a Normal Tonner Density Fig 4 38 Toner Density Monitoring b Low Toner Density 2 DEVELOPING TRAY The developing tray is curved to conform to the shape of the drum Developer is pumped to a ...

Page 136: ... The squeezing roller located at the after development edge of the developing tray serves two functions The primary function is to remove free floating toner particles from the dis persant on the drum surface as the drum departs the developing tray Without this cleaning action contamination of the image background will result as the drum passes in front of the negative corona As a secondary functi...

Page 137: ...sly mentioned components are mounted These components are controlled by the additional elements found on the underside of the cover shown in Fig 4 41 io Assembly Release Handle Toner Bottle Valve Entry Hole Toner Bottle Valve Trip Lever Premix Bottle Valve Entry Hole Wire for Lowering Squeezing Roller Connecting Rod for Moving Toner Bottle Valve Trip Lever g 9 10 Toner Replenishment Lever Developi...

Page 138: ...of developer is shown in Fig 4 2 Toner Bottle Toner Hole i Dispersant Bottle Dispersant Hole Developer Reservoir Developer Pump Motor Upper Surface of Drum ATR Subass y Density detector Developing Tray Fig 4 42 Circulation of Developer in the NP 70 b Toner Replenishing Mechanism The replenishing mechanism consists of the components which cause the feeding of toner as directed by the ATR circuit Th...

Page 139: ... lever motions result in the upward pivot action of the toner valve trip lever to release concentrated toner into the Developer Assembly The toner valve ac tuated is part of the cap of the concentrated toner bottle mounted on the front end of the Developer Assembly Fig 4 44 depicts these actions Toner Replenishment Lever Connecting Rod a Normal Density b Insufficient Density Fig 4 44 Toner Repleni...

Page 140: ... and drum damage a level monitoring float is attached to the bottom of the reservoir This float operates as follows a When the quantity of developer is at the normal level microswitch MS12 is actuated as illustrated in Fig 4 45 MS12 Fig 4 45 Normal Developer Level b If copying operation is continued with an empty dispersant bottle a lowering of the de veloper level results c When the developer qua...

Page 141: ...racket Fig 4 47 Reservoir Cover Underside View a Remove the reservoir cover from the Developer Assembly Pulley Mounting Bracket b Remove the retaining ring astrisk marked in Fig 4 47 from each of the four 4 com pression spring shafts c Remove the wire retaining bracket and retaining rings from the pulley mounting bracket shown in Fig 4 7 d Disconnect the tray lowering wire at the wire mounting stu...

Page 142: ...aching hardware in the following manner reference Fig 4 48 Roller Pivot Housing Spacer Roller Cleaner Mount Squeezing Roller Spacer Spacer Roller Roller Pivot Housing Note marked items are part of the Roller Pivot Housing Stop Screw Fig 4 48 Components of Squeezing Roller Detailed Spacer Roller Squeezing Roller Drive Gear Second Printing une 1974 CANON INC ...

Page 143: ...CING ACTIONS 1 TONER REPLENISHMENT LEVER ADJUSTMENT To ensure that toner replenishment actions are adequate perform the following reference Fig 4 49 a Remove the Developer Assembly from the copier and detach the cap from the toner bottle b Fit this cap into the valve entry hole so as to simulate the same condition as that of a toner bottle inserted c Pull the replenishment lever and observe the am...

Page 144: ...nd move it in the arrow direction appropriate for correcting the roller position tl O O Fig 4 SO Squeezing Roller Adjustment Shift the adjust screw toward the mark Shift the adjust screw toward the a mark Roller will lower Roller will rise Rear End Adjust Screw Front End Adjust Screw 3 DEVELOPER FLOAT ADJUSTMENT The range of detection can be adjusted by changing the position of the trip arm on the...

Page 145: ...t Adjustment 4 ATR SUBASSEMBLY CLEANING Due to the constant pumping of developer through the ATR Subassembly cleaning of the sub assembly housing is periodically necessary Perform this cleaning as follows a Wipe both walls of the slit molded into the underside of the ATR housing with Premix This is necessary to clean off the accumulated toner deposit See the Service Handbook for additional details...

Page 146: ...sembly operation a The skirt blade and the cleaner blade should be pressed against the sensitive drum with proper and constant pressure so that they can clean the drum completely and correctly b The skirt blade and the cleaner blade must not have any imperfections on the edge touch ing the drum surface c During the rotation of the drum there should be no harsh noises caused by the blades rubbing a...

Page 147: ...NP 70 4 45 0 c N U b Y Q Fig 4 53 Drum Cleaner Assembly Main Components Exploded View CANON INC Second Printing lune 1974 ...

Page 148: ...wo plates are mounted between the two blade portions They each have an overhanging finger which contacts the ends of the cleaner blade one at each end These fingers prevent leakage of developer from the ends of the cleaner blade and thus should contact their re spective ends of the blade 4 7 3 REMOVAL INSTALLATION ACTIONS The following points should be considered when performing replacement action...

Page 149: ...nt to the blade drum contact point Do this slowly and with uniform speed measuring the value on the balance while the inside sheet is sliding see Fig 4 54 e Measure three points front center and back of cleaner blade contact repeating steps b d Pressure Adjust ment Plate Spring Balance Pressure Receiving Sheets Locking Arm Knob Fig 4 54 Adjustment of Cleaner Blade Pressure AJ Cleaner Blade The pre...

Page 150: ...rt blade and holder on the assembly The skirt blade knobs should be tightened midway on the elongated mounting holes i Measure the pressure of the skirt blade against the drum using the same procedure as with the cleaner blade When placing the pressure receiving sheets under the skirt blade be careful not to insert them under the cleaner blade The specified pressure of the skirt blade should be at...

Page 151: ...s i i 1 CASSETTE CATCH When a cassette is inserted the catch fixes it firmly in the assembly frame by grasping the protruding rhombic shape projection on the bottom The cam like projection spreads the tensioned rollers which ride past the side peaks of the cam and hold the cassette fast 2 SWITCH MOUNT This component is the platform on which are mounted the microswitches MS11 MS15 used to indicate ...

Page 152: ...ssary perform the following after installation 1 ADJUSTMENTS The separation belt should contact the paper at a position 3 5 0 5 mm inward from the Copier Front edge of the paper Also the width of the no image area formed by the De veloper Assembly scraper blade should be 7 8 mm If either need adjustment perform the following a If the no image area is wider than specification slide the assembly fra...

Page 153: ...rmly so that only the top sheet of paper is fed by the pickup roller As the difference in paper sizes requires changes in copier operation the cassettes are used as a triggering device for switching over the circuitry for change When the half size cassettes A4 and BS are inserted into position a cam protruding from the bottom of each cassette actuates microswitch MSl 1 This switches the electrical...

Page 154: ...f coils Diameter of wire mm Total length mm A3 97 5922 10 0 1 2 71 5 B4 97 5923 11 0 1 2 75 A4 97 5924 10 0 1 0 79 BS 97 5925 10 5 1 0 84 5 Letter 97 5924 10 0 1 0 79 Universal 97 5924 10 0 1 0 79 Table 4 3 Spring Specifications 4 9 3 REMOVAL INSTALLATION ACTIONS The Cassette Assemblies are designed for easy slip in slip out use However whenever replac ing be sure that the cassette is firmly posit...

Page 155: ...0 1200 100 Universal 400 100 1200 100 Table 4 4 Spring Pressure for Cassette Assemblies NOTICE 1 The universal casette can be used multi size copying paper that is A3 B4 11 x 17 legal foolscap and folio 2 When the universal cassette is used remove the paper rubber roller closest to the machine rear side so that a rubber roller does not touch the paper separation bracket CANON INC Second Printing J...

Page 156: ...eration occurs as follows a The paper pickup roller is driven to rotate by the main motor through the drive mecha nism shown in Fig 4 58 The roller rotates continuously while the main motor is in operation Roller Drive Sprocket A Paper Pickup Roller Idler Sprocket Ladder Chain _ Gear Driving Roller Drive Sprocket Sprocket B Pickup Roller Drive Shaft Fig 458 Pickup Roller Rotation Drive rive Chain ...

Page 157: ...ven the rotation of clutch gear B is conveyed to the paper feed cam through the paper feed Cam control clutch iii The paper feed cam rotates and depresses the up down arm iv The pickup arm pivot shaft is rotated by the up down control arm in the direction shown in Fig 4 59 because the shaft is secured to the arm by a setscrew v At the same time the up down actuator on the pickup arm pivot shaft is...

Page 158: ...kup Roller Up Down Drive b Roller Lowered Copy Paper c As paper is picked up it is fed toward the feed timing roller to await feeding into the machine for image transfer This timing roller is driven by clutch gear A through the timing roller control clutch The control comes from the operation of solenoid SLS These components are shown in Fig 4 61 Pressure Roller Feed Timing Roller Paper Feed Gear ...

Page 159: ...otch in the collar of the paper feed cam to stop it as shown in Fig 4 62 Paper Feed Cam Paper Feed Cam Control Clutch Clutch Gear SL4 OFF Controller D Fig 4 62 Controller Assembly Operation AJ ii With SLS ON controller A is de tached from the timing roller con trol clutch which conveys the rota tion of clutch gear A to the timing roller However controller B presses against the inner notch of the t...

Page 160: ...4 Paper Feed Cam Clutch Gear B j ice Controller D Paper Feed Cam Control Clutch Fig 4 64 Controller Assembly Operation CJ v As SLS turns OFF controller B comes out of the notch in the timing disk permitting the disk to turn Controller A will come down and contact the disk and after approximately one revolution the disk will stop Controller A SLS OFF Controller B Fig 465 Controller Assembly Operati...

Page 161: ...OFF Spring B Inner Notch of Timing Disk Timing Roller Control Clutch Clutch Gear A Controller A Fig 4 66 Controller Assembly Operation EJ vii The paper which is advanced by the pickup roller is stopped by the timing roller as the latter is stopped Thus the paper is buckl ed as shown in Fig 467 At this time the paper feed signal is finished causing SLS to turn ON and SL4 to turn OFF Timing Roller S...

Page 162: ...iming disk and stops the disk when it falls into the inner notch At this point the disk is at its normal position as shown in Fig 4 68 a Feed Start Position b Nornial Position Fig 68 Controller Assembly Operation GJ ix When controller D falls into the notch of the paper feed cam collar it presses the control clutch to stop rotation At this time the up down control arm is in the hollow portion of t...

Page 163: ...oller rotates until controller 1 falls into the outer notch 4 ON OFF Stops Turns Stops Turns Timing roller stops with timing disk one rotation after the signal OFF ON Turns Turns Tums Turns Paper feed cam turns until controller 4 falls into the notch Raised OFF ON Turns Turns and is raised Stops Stops When paper feed cam stops pickup roller is at its highest position Copy paper is pressed upward b...

Page 164: ...rol Arm Fig 4 70 Paper Pickup Roller Assembly Main Components 1 PAPER FEED CAM The operation of this cam results in the up and down action of the paper pickup roller 2 PAPER PICKUP ROLLER This component is driven down onto the Paper Cassette Assembly to advance one sheet of paper for each copy reproduced Due to the nature of the assembly construction this roller rotates whenever the main motor is ...

Page 165: ...N REMOVAL When performing repair actions it may be necessary to remove the drive chain before Paper Feed Roller Assembly components This is performed as follows reference Fig 4 71 a After removing the rear cover loosen the tension sprocket and lower it to permit chain movement b Remove the drive chain O Chain Drive Sprocket Tension Sprocket A Drive Chain Tension Sprocket B Fig 4 71 Drive Chain Rem...

Page 166: ...E marked items form the Control Clutch Timing Disk Inner Notch Spring Retaining Collar Clutch action Ring Clutch Sprong Clutch Gear A Retaining Ring Fig 4 72 Timing roller Drive Main Components a After removing the copier rear cover remove the drive chain as explained in 4 10 3 b Remove the retaining ring from the shaft c While holding the timing roller control clutch draw clutch gear A from the s...

Page 167: ... is compressed and then pulling it out see Fig 4 74 Inner Notch Timing Disk Outer Notch Clutch action Ring Fig 4 74 Timing Roller Drive Disassembly BJ f Remove the remaining components from the shaft Clutch Spring Reassembly is performed by repeating the previous steps in reverse order When doing this however be sure to turn the spring in the same direction as previously to unsure spring compressi...

Page 168: ...ing Clutch Spring Compression Spring Clutch Gear B Gear Retaining Collar Fig 4 75 Paper Feed Cam Drive Main Components a Mark the position of the Paper Feed Controller Assembly on the copier frame and then remove the assembly Be careful not to damage any controllers by striking them against gears b Remove the gear retaining collar c Draw the cam control clutch and clutch gear B as a unit from the ...

Page 169: ...sassembly AJ Clutch Gear B Gear Retaining Collar d Draw out clutch gear B by turning it counterclockwise while holding the control clutch as shown in Fig 4 77 Hold Clutch Gear B n Control Clutch Fig 4 77 Paper Feed Cam Drive Disassembly BJ CANON INC Second Printing June 1974 ...

Page 170: ...isassembly CJ f Extract the compression spring from the pickup control cam by turning the spring counterclockwise as shown in Fig 4 79 Then check the shape of the spring Compression Spring Paper Feed Cam Fig 4 79 Paper Feed Cam Drive Disassembly DJ Reassembly is performed by repeating the previous steps in reverse order When doing this however be sure to turn the springs in the same direction as p...

Page 171: ...e solenoid mounting plate position until these para meters are met 4 PICKUP ROLLER SPACING ADJUSTMENTS The spacing of the rubber pickup rollers on their shaft should correspond to the measure ments given in Fig 4 81 Should any adjustment be necessary loosen the setscrew secur ing the roller to the shaft and slide the roller to the correct position then resecure the roller C 228 4 148 3 35 2 183 2 ...

Page 172: ...r Sprocket Front Mounting Plate F I Paper Cassette Support Pickup Rubber Roller Roller Shaft 2 0 mm Paper Cassette Support Fig 4 82 Pickup Roller Height Should this spacing require adjustment perform as follows reference Fig 4 83 a Depress the COPY button to start a copy cycle b When the pickup roller drops down for paper disconnect power by UNPLUGGING the copier turning OFF the power switch does ...

Page 173: ...Pickup Roller Height Adjustment Adjust Screw Pickup Arm Brace f After completing the adjustment restore the copier to normal operation by installing the Drum Unit Cassette Assembly and Developer Assembly 6 LUBRICATION Apply lubricating oil TET 27 to the point indicated in Fig 4 84 and 4 85 Lubricating Points 1 r Fig 4 84 Paper Feed Cam Drive Lubrication CANON INC Second Printing une 1974 ...

Page 174: ...4 72 NP 70 Lubricating Points Fig 4 85 Timing roller Drive Lubrication See the NP 70 Service Handbook for additional details concerning assembly lubrication Second Printing une 1974 CANON INC ...

Page 175: ... fed from the paper cassette will pass across this assembly for fixing and residual charge elimination The paper is then carried out to the copy tray 4 11 2 ASSEMBLY MAIN COMPONENTS Delivery Roller 1 Delivery Roller 2 Outer Cover Main Body Separation Roller Copy Paper Guide Partitioning Plate Delivery Guide Fig 4 86 Copy Conveying Assembly Main Components CANON INC Second Printing lune 1974 ...

Page 176: ...ivery roller 2 for delivery into the copy tray At the same time any residual charge is removed from copies by an AC corona called the residual charge eliminator a Delivery Roller 1 Delivery roller 1 is composed of a main roller and an auxiliary roller positioned directly above The lower roller is made up of 4 rubber rollers on a shaft and the upper roller is composed of 4 plastic rollers also on a...

Page 177: ...jam condition Residual charge is removed from copying paper by the residual charge eliminator and the check for normal paper passage is performed by the jam detection lamp L4 4 PARTITIONING PLATE Fig 4 89 illustrates an outer view of the partitioning plate This plate guides copying paper coming from the separation roller The portions circled in Fig 4 89 serve as air ducts for aiding separation of ...

Page 178: ...engaging its hanger stay from the locking hook d Remove the Drum Assembly e Remove the Transfer Corona Assembly and the Paper Separating Subassembly fj Raise the Copy Conveying Assembly back to its original position and remove the Heater Assembly g Disconnect the high voltage connector of the Transfer Corona Assembly and put it into the Copy Conveying Assembly Delivery Roller 2 Hanger Stay Upper L...

Page 179: ...ig 4 91 Pivot Shaft Removal Pivot Shaft Retaining Washer Copier Front Plate 2 COPY CONVEYING ASSEMBLY INSTALLATION To place the Copy Conveying Assembly back in the copier after maintenance is completed perform the following a Place the Copy Conveying Assembly back in position in the copier setting its hanger stay on the locking hook to raise the assembly b Insert the pivot shaft through the hole i...

Page 180: ...e the access doors 4 11 4 REPAIR SERVICING ACTIONS 1 COPY PAPER GUIDE REPAIR Whenever replacement of the guide wire in the copy paper guide is necessary perform the wire installation as follows a Cut a section of stainless steel wire to a length of 1745 1755 mm 1750 5 mm b Wind one end of the wire twice clockwise around screw A 0 0 Screw A O7 10 11 1 15 O9 12 13 18 19 2 3 Fig 4 92 Copy Paper Guide...

Page 181: ...In the event that paper fails to flow smoothly from the separation roller onto the Copy Con veying Assembly body the following adjustment may be necessary Reference Rod 14 Side Plate Top Edge Partitioning Plate Adjustment Screw Separation Roller Fig 4 94 Partitioning Plate Height Adjustment a Place a straight rod plate or the like as a reference on the top edge of both side plates of the Copy Conv...

Page 182: ...ace between the rubber roller portion of the separation roller and the drum surface Turning screw B clockwise Widens the clearance Turning screw B counterclockwise Narrows the clearance 0 m Screw B Screw A Fig 4 95 Positions of Screws A and B 5 GEAR BACKLASH ADJUSTMENT This backlash requires no adjustment except when the whole Copy Conveying Assembly is replaced with a new one Turning screw A cloc...

Page 183: ...from the drum after the completion of transfer As this subassembly separates the machine front edge of the paper from the drum it carries the paper across the separation roller to the Heater Assembly for fixing Drum 1 1 1 I I I I I 1 I Separation Roller Transfer Corona Paper Feed i Guide Plates Fig 4 96 Movement ofSeparation Belt from copier rear CANON INC Second Printing lune 1974 ...

Page 184: ...n the roller and the sepaza tion belt As the belt now moves over the sepazation roller rather than the drum surface the machine front end of the paper is drawn away from the drum The remainder of the paper is drawn away from the drum due to the airflow within the copier see section 4 14 Blower Fan Assemblies resulting in a sepazation of the paper along its entire leading edge This process will con...

Page 185: ... screws move the separation belt from the separation roller to the installation stud Do this by passing a fmger between the belt and roller and while controlling belt tension with the release lever pull the belt outward until it can be seated in the installation stud groove c When removing installing the subassembly be careful not to touch the drum surface d After installation make sure that the b...

Page 186: ...has no twists after it is installed on the subassembly Twists if present during operation will cause paper jamming or belt breakage 4 12 4 REPAIR SERVICING ACTIONS 1 CLEANING As the separation belt is constantly in contact with the drum it becomes dirty after a period of time Thus the belt should be cleaned and the cleaner pad changed periodically to pre vent belt marks from appearing on the repro...

Page 187: ...input AC voltage of the model of NP 70 being used Table 4 5 indicates these differences Line Voltage Heater Designation Configuration Circuit Diagram 100V H1 H2 H3 parallel H1 ON continuously H2 H3 controlled by H C Ckt r r I i H C ckt I 220V 240V H1 H2 Series H1 H2 controlled by H C Ckt I i II i I H C I ckt _ _ L___J It should be noted that the heater operation is controlled so that the outer pla...

Page 188: ...en the temperature of the assembly rises abnormally high the temperature fuse melts to break the heater circuit This fuse melts at 150 C 2 HEATER ELEMENT SECTIONS There are two of these section in each Heater Assembly They are constructed of mica with one or two nichrome heater elements within Fig 4 99 shows the two types of elements used in NP 70 machines 400W OOW f Mica Layer OM a Dual lement Ty...

Page 189: ...TIONS When removing installing the Heater Assembly be sure to swing the heater stopper bracket mounted on the Copy Conveying Assembly aside to permit free movement of the assembly 4 13 4 REPAIR SERVICING ACTIONS 1 CLEANING As the upper heat dispersion plate is constantly contacting wet copies toner builds up rapid ly To ensure that the heater continues to operate efficiently this build up should b...

Page 190: ...tion of dis persant fumes resulting from the fixing process The Fan Assembly located at the right front end of the copier operates when temperatures are above 60 C This operation is designed to prevent excessive dispersant evaporation due to heat within the copier 4 14 2 ASSEMBLY MAIN COMPONENTS The following three figures show the main components of the three assemblies Guide Plate Drum Housing L...

Page 191: ...r Input Blower Motor Blade Drum Rear Mounting Plate Fig 4 101 Air input Blower Assembly Main Components Fan Blade Fig 4 102 Fan Assembly Main Components Guide Plate Fan Motor Printed ckt Unit CANON INC Second Printing lune 1974 ...

Page 192: ...NS Replacement of these assemblies requires no special procedures with the exception of the following a The replacement of the Suction Blower Assembly requires the removal of the Copy Con veying Assembly from the copier body b Be sure to unplug all appropriate connectors before removing any of the assemblies 4 144 REPAIR SERVICING ACTIONS 1 ADJUSTMENTS It is important that the blower assembly blad...

Page 193: ...NP 70 4 91 Drum Housing Motor Screws Dtum Pivot Blade Drum Fig 4 103 Blower Blade Drum Adjustment CANON INC Second Printing June 1974 ...

Page 194: ... device driven by the movement of the copy board with each copy reproduced the copyboard advances the mechanism until the mecha nism resets to stop further copying 4 15 2 ASSEMBLY MAIN COMPONENTS Copy Button Stop Button Selector Dial Click Wheel Release Lever Click Lever Pawl Drive Plate Mounting Plate Release Arm Shaft Guide Counter Pawl Microswitch MS7 NOTE marked items Ratchet Wheel form the Dr...

Page 195: ...f the selector is complex the following operation explanation 25 copies or less of the remaining components is provided a Rotation of the copy selector dial sets the click wheel to its reference position held fast by the click lever b Due to torsion spring force the ratchet wheel A stud will remain positioned against the B stopper of the click wheel as shown in Fig 4 105 Ratchet Wheel Fig 4 105 Ra...

Page 196: ...cs The forward movement of the copyboard frees the selector advance lever on the copier body and due to tension the pawl drive plate moves to ad vance the ratchet wheel As the wheel moves projection A see Fig 4106 slips over the advancing tooth to prevent the wheel from returning see Fig 4 107 copyboard Locking Cam Selector Advance Lever Drive Stud Counter Pawl Link Stud Drive Stud Pawl Drive Plat...

Page 197: ...en clearly in Fig Fig 4 108 Pawl Drive Plate Counter Pawl Ratchet Wheel Disengaging Stud Fig 4 108 Copy Selector Operation CJ f The back and forth motion of the copyboard will cause the copy selector to advance one position for each copy made As the last copy is started the release arm trip projection on the ratchet wheel lifts the release arm The action thus frees the start shaft and microswitch ...

Page 198: ...d copying as shown in Fig 4 110 Start Shaft Start Shaft Stud Stop Button Release Arm Release Lever Shaft Guide Fig 4 110 Stop Button Operation 4 15 3 REMOVAL INSTALLATION ACTIONS Whenever installing the Copy Selector Subassembly make sure that the drive stud on the un derside of the Drive Plate Unit is positioned correctly in relationship to the link stud of the selector advance lever Fig 4 111 sh...

Page 199: ...ews and insert the start shaft with the shaft stud in the groove of the shaft guide b Place the torsion spring over the shaft and attach one end of the spring through the slot in the shaft guide c Place the ratchet wheel on the shaft and with sharp pointed tweezers hook the spring end on the ratchet wheel d Insert the shaft sleeve over the shaft with the collar flush to the ratchet wheel e Note th...

Page 200: ...tioning Top View g During the assembly of the remaining components hold the ratchet wheel in position so that the tension on the spring is maintained 2 MICROSWITCH ADJUSTMENT To prevent damage to microswitch MS7 the position of the switch body should be adjusted so that switch plunger travel is only about 1 mm This travel is defined as the difference be tween the plunger height when the COPY butto...

Page 201: ...the machine a When either the upper or front left access door is opened all power will be cut to the machine to prevent personnel injury b Should a jam condition occur in the machine drive power is cut to prevent equipment damage 4 16 2 ASSEMBLY MAIN COMPONENTS Jam Stop Group Door Switch Group Ass y Main Plate Ass y Main Cover Fig 4 114 Safety Assembly Main Components Circuit Breaker CANON INC Sec...

Page 202: ...cally to cut power to the machine When the breaker operates reset lever OFF side examine the machine to determine the cause before turning the reset lever back to the ON side 3 DOOR SWITCH GROUP Upper Door Upper Door Safety Lever Front Door Safety Lever Fig 4115 Door Switch Group Main Components The door switch group contains two microswitches which when released cut all power to the copier These ...

Page 203: ...FF Lever Arm Upper Door Safety Lever Front Door Fig 4 116 Door Switch Group Operation AJ Front Safety Lever b When the front door is closed the front safety lever rotates and pulls the link wire toward the right as shown in the Fig 4 117 This causes the trip lever to rotate but as it is at such a high position it cannot actuate the microswitches Upper Door OFF Microswitches Trip Lever Fig 4 117 Do...

Page 204: ... actuators of the two microswitches see Fig 4 118 Upper Door Upper Door Safety Lever Fig 4 118 Door Switch Group Operation CJ d If the front door is open while the upper door is closed the microswitch actuators will be released because the trip lever is not rotated see Fig 4 119 Upper Door Fig 4 119 Door Switch Group Operation DJ Second Printing June 1974 CANON INC ...

Page 205: ...the trip release lever is in the notch of the actuation trip lever as shown in Fig 4121 In this case the reset button is held down but under spring tension b Since the reset button is at its lower position the actuator trip lever is pressing MS6A 6B to their ON position and power is being supplied to the copier Stud of Trip Release Lever Reset Button Reset Button Arm Trip Release Lever Actuator Tr...

Page 206: ... and Illumination Assembly is broken to stop copying g Resetting of the power is accomplished by depressing the reset button 4 16 3 REMOVAL INSTALLATION ACTIONS Whenever removing the Safety Assembly first remove the copier left front door This is necessary to allow the assembly to be drawn out of the copier without damaging the levers protruding into the main body area 4 16 4 REPAIR SERVICING ACTI...

Page 207: ...release lever should be held firmly by the stud The position of SL7 should be adjusted so that it operates properly in the above two situations do this by loosening the retaining screws which secure SL7 and sliding the solenoid up or down see Fig 4124 b Position of MS6A MS6B Microswitches MS6A MS6B should be turned ON securely when the reset button is depressed Adjust the position of the microswit...

Page 208: ...ausing the return and forward drive sprockets to rotate As neither clutch is ON no further action occurs see Fig 4 125 C E1 OFF C 2 OFF Drive Chain Drive Sprockets Fig 4 125 Driving Mechanism Operation AJ b As the start cam begins the copy cycle the forward clutch C E 1 is energized c Activation of C 1 results in the wire driving pulley rotating to cause the copyboard to move forward see Fig 4 126...

Page 209: ... powered through the movement of chain A which connects the return clutch sprocket to the forward clutch sprocket see Fig 4 127 Chain A C2 2 ON Wire Driving Pulley Fig 4 127 Driving Mechanism Operation CJ g As the copyboard returns to the starting position it activates MS8 which breaks the circuit holding C 2 energized Thus C 2 stops operation h The copyboard will wait until the next start cam sig...

Page 210: ...moves forward Turns forward Turns forward ON Turns forward Turns backward OFF Turns forward MSlA y Copyboard moves backward t Turns backward Turns forward OFF Turns wad Turns backward ON Turns backward MS9 MS10 o v Stop folrward OFF Stop backward OFF Stop MS8 C S Clutch Sprocket D S Drive Sprocket C Clutch Fig 4 128 Copyboard Reciprocation Operation Second Printing lune 1974 CANON INC ...

Page 211: ... Forward Clutch Sprocket Chain A Return Clutch Spro ket Return Clutch C e2 Return Drive Sprocket Copyboard Wire Drive Chain Wire Driving Pulley Forward Drive Sprocket Fig 4 129 Copyboard Driving Mechanism Assembly Main Components CANON ANC Second Printing lune 1974 ...

Page 212: ...d while the other end draws the Copyboard in the return direction for additional information section 4 1 Copyboard Assembly 4 17 3 REMOVAL INSTALLATION ACTIONS The replacement procedures used for the Copyboard wire are included in section 4 1 Copy board Assembly 4 17 4 REPAIR SERVICING ACTIONS Adjustment procedures for the Copyboard wire are included in section 4 1 Copyboard Assembly Second Printi...

Page 213: ...NG DIAGRAM PROD NO 8 11154 55 1 OF 2 WIRING DIAGRAM PROD NO 8 11154 55 2 OF 2 WIRING DIAGRAM PROD NO 8 11156 57 WIRING DIAGRAM PROD NO 8 11158 84 APPENDIX B SPECIFIC CIRCUITS HEATER CONTROL CIRCUIT SCHEMATIC DIAGRAMS PRINTED CIRCUIT BOARD LAYOUTS 1 OF 3 PRINTED CIRCUIT BOARD LAYOUTS 2 OF 3 PRINTED CIRCUIT BOARD LAYOUTS 3 OF 3 APPENDIX C ELECTRICAL PARTS PARTS LIST COPIER COMMON COMPONENTS PARTS LI...

Page 214: ...NP 70 CANON INC ...

Page 215: ... FORWARD ONE 77 7 132 0 E HALF SIZE 195 5 COPYBOARD REVERS MOTION POSITION H 190 5 199 2 287 0 317 9 1243 1 283 8 COPYBOARD RETURN COPYBOARD CYCLE FULL COPYBOARD FORWARD SIZE 348 0 96 338 9 COPY OARD STO POSI ION HALF 32 6 2 350 2 COPYBOARD MOTION POSI 345 2 354 0 EVER ON f LONE DRUM REVOLUTION 5E ULL 540 180 630 270 1194 8 220 2 n 190 5 199 2 609 7 249 7 235 4 513 9 554 6 153 9 194 6 COPYBOAR RET...

Page 216: ...NP 70 CANON INC ...

Page 217: ...2 Ti 5 O6 Try c av voRD IRE77aZy Js s J Rte R I I Ta Tyr I TH3 I Tsui a I I R3v3 R oS Tr 4 D3o Kam T 7 4 4302 Rsa7 4303 R3o2 R3d4 R C Td 3 PC4 R3a L2 I PCq L TJ 3 A7R _ ___ RS PC7a Tirr Jas i R25 m Q4 cPOlar R5 R7B m R7q z PC CdS PCs JJ I SI Tss 7 T9s S M 4TER Nr47TCONT L R 3 R30 Stb s O 3 J z b 2 PCJ R3 4 R3 2 I SL C 3 R37 t c rR 3Ra5 q3 SM2 I2 6 sc av yR7 cR36 R3H D u 3 D 4 f Pa9 O 5 R Z C r I C...

Page 218: ...NP 70 CANON INC ...

Page 219: ...5 9 Kso Tr6 T 2 Cc19c N FAN TB4 447 K l D Sp i4 FPC E v Z RiZy R 7 Pi1B C3 Q4B r a R2B S vR5 R29 Mnr L2 yR26 1 15 1CdS RS PCi 5 k Pci L JJ PCa Jsr Jasi cP OrgvE t S 3R F R3 O R CUo J a 4pC J I 2 I I _ IMS 2 _T e Ji z L El LA1 ER SUPPLY Ra5 3 iS I Rb sc av vR7 R36 R3B D 3 O 5 D 4 AA R39 I C 3 Ci2 t Ts I J o s L 37 C30 vv R b 01 4 3 i vR Ci D 3 IDa7 Rira CAa 40 C 5 R42 444 LY6 D 7 t I R vs R PL LADY...

Page 220: ...NP 70 CANON INC ...

Page 221: ...VR R73 f 42B RBO v RB3 C13 J37 p NE4TER CONTROL CKT T 2 b Tit 7 J I Q T1J J J Tlra r VR30 Tz Tya TH3 E TlpF DL REAOY nu _ Tio q r BK i EG G 77C F EGD RAD 47LVP j JFJ 712 3 JP C y _ I Jir r T n I i TiiI JII I I s 7F6 rFs f I nTig tr 1 Tilt Jti 6 Tri Tztia T J I I 1 I I A Tz J 9 K30 Tx YTi d I TJa2 J rB WK I r twr ANEIOP f IR n p v Rl ST2 p 7P SyNeR S p BLOWZ Kd Y I YS 9p 1 T y P T2BY Jri Y I v x060...

Page 222: ... I I T8 I I I I T9 I I L_ TAM DETECTION CKT J 1 I I T RFCIPf OCATION I carvTRpL I I I I cKT i I I I Tz I r3 r L ____J r TZ 5 B 0 PL P 0 TXG K 0 eB eL 0 T 7a 2 PK r J 7a 3 PK T3 B RD TB BK TB7 RD 0 r r T 7 9 YE 0 Ti7 B OR TBB BL T37 3 GY 0 T37 4 iY Ti7 4Y 8 T BL T3 S PK T3 6 PK Q TB6 BR rB RD S3 T3 YE r B L T3 7 OR J 3 O Ti3 2 YE TB 6 BL 0 TX 3 PK 0 T 2 BL MS A om MS oM YY M53 4 N0 r r9 3 YE 522 2 ...

Page 223: ...NP 70 CANON INC ...

Page 224: ...B 4 CM BK MAI V MOTOR ASS s _ MS COMI T d 6 GY C NC TJ4 yE C NOQM rBr Ro _ 3 C NC r o T YE uv OM TB3 8 t J3 2 C NC J d YE NJOM TB7 RD T 32 6 GY T3 T GY 3 BK swa i BR RSA JR RS Na 3 wN MS A MSZA MS3A MS4 MSS F J37 M FJ T3S MJ L BK Tz9 PK RD OI E ALL E XR SURE LAMP JPi J73 RD T2JZ Ro TF RD Fl T34 Ml EFR J JFZ J73 3 BL FJ TZ3 M c PL PL 2 e PL3 O 0 h PL4 T3 3 PK T2 2J 9 TB E S r tom t 0 szrea a 0 J O ...

Page 225: ... L____J TIMER I cKr I L J D l FLOP qSS Y r r i j T 4M j I IoErecTioiv I CKT L I PEC SCAT ONI CONTROL I CKT L FJ J S M r T302 FM3 J L4 T 3 BK 7 7 4 BL T p w MJ J26 FJ ri7 a rB BK TB414 fiJBK rar H BK r TB6 BR 0 T3S 2 BBB B J32 B GY T323 OR J9 5 YE 0 r T 6 1 r I yEgrER Ass Y rH Th 2 r H H 2 j vs I I L T27 T27 3 T27 BK T 7 wra O T27 2 IrH T 7 2 wH J2B BK 7 7 WH 0 0 J 9 9L T27 2 N 2 H3 L4 BR Ti7 B oR ...

Page 226: ... r IJ 2 Jio J7 J8 J9 T 32 J J2 Jd r I NEATER I CONTROL i CXT IrzEtrlr7cq TIOKI I CKT I I I I I j r 1 7 ME P I I I I GXT I I I I I JAM DETECTION I I C fT i I I I L _ J IREC PROCATiov I CONTROL I CKT OL V LO ER Ass y F J S M J302 lM3 32 8 4J Q J1aQ wy O rB BK r O rB6 BR O T93 1 3 rB6 BL 32 0 oR o J32 3 YE p rB2 wH J36 Q P j6 7 PK J 6 J 3 MS 2 HEATER ASSN TB3BK T42 IV Y O J27 1 J27 2 0 O p N F Ty J T...

Page 227: ...D231 R236 D234 L23I R23B R740 C233 R 39 Heater Control Circuit Zero Cross Tsz Heater Control Circuit 100VAC J32 I T32 2 1 TNI T32 3 R244 Heater Control Circuit Schematic Diagrams CANON INC Second Printing June 1974 ...

Page 228: ...NP 70 Jam Detection Circuit P C Assembly 1 Timer Circuit P C Assembly 2 CANON INC ...

Page 229: ...B 2 Rectification Circuit P C Assembly 3 Reciprocation Control Circuit P C Assembly 4 Printed Circuit Board Layouts 1 of 3 Second Printing June 1974 ...

Page 230: ...NP 70 Heater Control Circuit Zero Cross P C Assembly 5 Heater Control Circuit l OOVAC Only P C Assembly 5 CANON INC ...

Page 231: ...B 3 Heater Wait Control Circuit P C Assembly 6 Developer Temperature Control Circuit Machine Cooling Fan Assembly Printed Circuit Board Layouts 2 of 3 Second Printing June 1974 ...

Page 232: ...NP 70 B 4 A T R Circuit A T R Subassembly Printed Circuit Board Layouts 3 of 3 CANON INC Second Printing June 1974 ...

Page 233: ...l Photocell electrolytic electrolytic electrolytic electrolytic polyester film polyester film electrolytic polyester film polyester film electrolytic polyester film polyester film polyester film electrolytic polyester film polyester film polyester film polyester film electrolytic electrolytic electrolytic polyester film Cd5 Cd5 CdS Clutch forward driving Clutch return driving Counter half size she...

Page 234: ...Diode silicon Diode silicon Diode silicon Diode silicon Diode silicon Diode silicon Diode silicon Diode silicon Diode silicon Diode silicon Diode silicon Diode silicon Lamp fluorescent Lamp exposure Lamp exposure Fuse temperature sensitive Relay enclosed plug in Relay enclosed plug in Relay enclosed plug in Relay enclosed plug in Relay enclosed plug in Relay enclosed plug in Relay enclosed plug in...

Page 235: ...p action Circuit Breaker plunger reset Circuit Breaker plunger reset Lamp pilot yellow Lamp pilot orange Lamp pilot orange Transistor NPN Transistor NPN Transistor NPN Transistor NPN Transistor NPN Semiconductor Device I C Semiconductor Device SCR Semiconductor Device PUT Semiconductor Device SCR Transistor NPN Transistor NPN Transistor NPN Transistor NPN Transistor PNP Semiconductor Device SCR Se...

Page 236: ...stor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor NPN PNP PNP NPN carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film c...

Page 237: ...Resisj or Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor Resistor carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon silm carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film carbon film ...

Page 238: ...sistor carbon film 680521 4W SL 1 X62 1241 Solenoid D C DS128 SL4 X62 1240 Solenoid D C DS08 SL5 X62 1240 Solenoid D C DS08 SL6 X62 12 39 Solenoid D C DSl OB SL7 X62 1240 Solenoid D C D508 5M2 X62 0824 Switch thermostatic 15 C ON TH2 X62 7427 The rmistor probe type TH3 X62 7431 Thermistor probe type VR1 X64 4349 Resistor variable 2kS2 VR2 X64 4348 Resistor variable 1kSt VR5 X64 2447 Resistor varia...

Page 239: ...ord input voltage 250VAC l0A PL2 X62 7508 Lamp pilot red 250VAC PL5 X62 7509 Lamp pilot orange 250VAC 5T1 X61 1304 Stabilizer voltage ST2 X61 1305 Stabilizer voltage T201 X61 1308 Transformer pulse Prod No 8 11156 57 ES X62 1528 Starter fluorescent lamp FM1 X61 2138 Motor blade drum drive FM2 X61 2138 Motor blade drum drive FM3 X 61 2048 Motor cooling fan H1 X61 7148 Element heating 100VAC 250W H2...

Page 240: ...ansformer high voltage LVT X61 1308 Transformer low voltage M1 X61 2177 Motor copier main drive M2 X61 2180 Motor developer pump NFB1 X61 1073 Circuit Breaker plunger reset 250VAC 8A NFB2 X62 1074 Circuit Breaker plunger reset 250VAC lA P X61 9139 Plug Cord input voltage 250VAC l0A PL2 X62 7508 Lamp pilot red 250VAC PL5 X62 7509 Lamp pilot orange 250VAC 5T1 X61 1304 Stabilizer voltage ST2 X61 1305...

Page 241: ... R231 X64 0425 Resistor carbon film 15kS21 4W R232 X64 0392 Resistor carbon film 5 6kSZ1 4W R233 X64 0392 Resistor carbon film 5 6kS21 4W R234 X64 0360 Resistor carbon film 1 kStl 2W R235 X64 0470 Resistor carbon film lOkStl 4W R236 X64 0425 Resistor carbon film 15kSZ1 4W R237 X64 0392 Resistor carbon film 5 6kSZ1 4W R238 X64 0360 Resistor carbon film 1kS21 2W R239 X64 0425 Resistor carbon film 15...

Page 242: ...r carbon film 5 1kSZ1 4W R707 X64 0975 Resistor carbon film 5 1kSt 1 4W R108 X64 0472 Resistor carbon film 22kSt1 4W R109 X64 0392 Resistor carbon film 5 6k 1 4W R110 X64 0472 Resistor carbon film 22kSt1 4W R111 X64 0776 Resistor carbon film 3 3kS21 4W R112 X64 0775 Resistor carbon film 5601Z1 4W R113_ X64 3105 Resistor carbon film 20SZ1 2W TH1 X62 8997 Thermistor Probe Unit Tp X62 1436 Transforme...

Page 243: ...CANON INC PUB ME7606 2030A ...