Service Manual
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... are given. Multifeeding (manual) - Copying speed (cpm) 8 10 10 12 COPYRIGHT © 1994 CANON INC. This Service Manual consists of the following respects: Model PC720 PC740 PC750 PC770 Singlefeeding (manual) - - In addition to the above chapters, this Service Manual contains a set of ... of its operation, disassembly, reassembly, and adjustment. CHAPTER 2 "COPYING PROCESS" deals with the inner workings of the copier associated with the generation of replacement parts and consumables. CHAPTER 6 "MAINTENANCE AND SERVICING" contains tables of copies. INTRODUCTION This...
... are given. Multifeeding (manual) - Copying speed (cpm) 8 10 10 12 COPYRIGHT © 1994 CANON INC. This Service Manual consists of the following respects: Model PC720 PC740 PC750 PC770 Singlefeeding (manual) - - In addition to the above chapters, this Service Manual contains a set of ... of its operation, disassembly, reassembly, and adjustment. CHAPTER 2 "COPYING PROCESS" deals with the inner workings of the copier associated with the generation of replacement parts and consumables. CHAPTER 6 "MAINTENANCE AND SERVICING" contains tables of copies. INTRODUCTION This...
Service Manual
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... 1-1 III. BASIC OPERATION 3-1 VI. IMAGE FORMATION SYSTEM 3-17 ADJUSTMENTS 3-64 IV. EXTERNALS 4-1 V. SELECTING THE SITE II. CANON PC7201740,11501170 REV.O AUG. 1994 PRINTED IN JAPAN (IMPRIME AU JAPON) OPERATIONS 1-8 CHAPTER 2 COPYING PROCESS I . STANDARDS AND III. ...EXPOSURE SYSTEM 3-11 VII. RELOCATING THE COPIER 5-7 5-2 COPYRIGHT © 1994 CANON INC. POWER SUPPLY 3-60 II. ELECTRICAL SYSTEM 4-33 CHAPTER 5 INSTALLATION I. PICK-UP/FEEDING SYSTEM 4-17 VI. SELF DIAGNOSIS...
... 1-1 III. BASIC OPERATION 3-1 VI. IMAGE FORMATION SYSTEM 3-17 ADJUSTMENTS 3-64 IV. EXTERNALS 4-1 V. SELECTING THE SITE II. CANON PC7201740,11501170 REV.O AUG. 1994 PRINTED IN JAPAN (IMPRIME AU JAPON) OPERATIONS 1-8 CHAPTER 2 COPYING PROCESS I . STANDARDS AND III. ...EXPOSURE SYSTEM 3-11 VII. RELOCATING THE COPIER 5-7 5-2 COPYRIGHT © 1994 CANON INC. POWER SUPPLY 3-60 II. ELECTRICAL SYSTEM 4-33 CHAPTER 5 INSTALLATION I. PICK-UP/FEEDING SYSTEM 4-17 VI. SELF DIAGNOSIS...
Service Manual
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GENERAL DESCRIPTION - COPYRIGHT @ 1994 CANON INC. Designed with considerations for ease in maintenance work to make jam removal easy. average...entity-the user may be used (manual). 6. Extra touches to the copies. • The black toner cartridge may be selected. 2. CANON PC7201740/7501770 REV.0 AUG.1994 PRINTED IN JAPAN fMPRIME AU JAPAN) 1 - 1 Integrated cartridge for the environment. • The use ... use of a charging roller helps to limit the generation of existing machines) 3. Separate top unit. • The copier's top unit may be given an extra finish. 7. I.
GENERAL DESCRIPTION - COPYRIGHT @ 1994 CANON INC. Designed with considerations for ease in maintenance work to make jam removal easy. average...entity-the user may be used (manual). 6. Extra touches to the copies. • The black toner cartridge may be selected. 2. CANON PC7201740/7501770 REV.0 AUG.1994 PRINTED IN JAPAN fMPRIME AU JAPAN) 1 - 1 Integrated cartridge for the environment. • The use ... use of a charging roller helps to limit the generation of existing machines) 3. Separate top unit. • The copier's top unit may be given an extra finish. 7. I.
Service Manual
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After copying operation is over, the auto power-off mechanism becomes activated if the copier is delivered. Figure 1-403 2) Place an original on the singlefeeder. • You must not set the ratio between 70% and 141% in 1% increments. then, check ...; If paper jams, the JAM indicator will flash and copying operation stops; A4/LTR B5►A5/STMT 4 ► A5 (AB/Inch- COPYRIGHT © 1994 CANON INC. CANON PC72017407501770 REV.0 AUG.1994 PRINTED IN JAPAN (IMPRIME AU JAPON) 1 - 11
After copying operation is over, the auto power-off mechanism becomes activated if the copier is delivered. Figure 1-403 2) Place an original on the singlefeeder. • You must not set the ratio between 70% and 141% in 1% increments. then, check ...; If paper jams, the JAM indicator will flash and copying operation stops; A4/LTR B5►A5/STMT 4 ► A5 (AB/Inch- COPYRIGHT © 1994 CANON INC. CANON PC72017407501770 REV.0 AUG.1994 PRINTED IN JAPAN (IMPRIME AU JAPON) 1 - 11
Service Manual
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... in order, and set the stack back in. C) Make sure that the cassette is paper in the cassette holder. 3) Press the Copy Start key. CANON PC720/T401759/770 REV.O AUG.1994 PRINTEDIN JAPANRout AU JAPONI 1 - 15 Adding Paper The Add Paper indictor 'P' turns on in response to the following conditions... inside the machine. 0 Remove the jam with care so as not to indicate the presence of paper, set in the cassette, go off, and the copier will make the remaining number of paper if it has torn. 1) Check the multifeeder for a jam. CDI Take out the stack of the multifeeder. 2) ...
... in order, and set the stack back in. C) Make sure that the cassette is paper in the cassette holder. 3) Press the Copy Start key. CANON PC720/T401759/770 REV.O AUG.1994 PRINTEDIN JAPANRout AU JAPONI 1 - 15 Adding Paper The Add Paper indictor 'P' turns on in response to the following conditions... inside the machine. 0 Remove the jam with care so as not to indicate the presence of paper, set in the cassette, go off, and the copier will make the remaining number of paper if it has torn. 1) Check the multifeeder for a jam. CDI Take out the stack of the multifeeder. 2) ...
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... the old cartridge out of use the cartridge, a new cartridge should be obtained. Replacing the Cartridge." 1 - 16 COPYRIGHT © 1994 CANONINC. CANON PC720840r/501770 REV.OAUG.1994 PRINTEDIN JAPAN0MPRIMEAU JAPON) functions. If the copy image has returned to normal, • Advise the user that, although he/she... the copy image will tend to use . to tam ,;an. When to Replace the Cartridge When the cartridge starts to run out of .lre copier, its capabili• ng this manua ACAUTIO - : In this manii' procedure AGES with this Ft if, personal in Figure 1-412 Go through...
... the old cartridge out of use the cartridge, a new cartridge should be obtained. Replacing the Cartridge." 1 - 16 COPYRIGHT © 1994 CANONINC. CANON PC720840r/501770 REV.OAUG.1994 PRINTEDIN JAPAN0MPRIMEAU JAPON) functions. If the copy image has returned to normal, • Advise the user that, although he/she... the copy image will tend to use . to tam ,;an. When to Replace the Cartridge When the cartridge starts to run out of .lre copier, its capabili• ng this manua ACAUTIO - : In this manii' procedure AGES with this Ft if, personal in Figure 1-412 Go through...
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then, rotate it about 90° several times. 5) Hold the cartridge with the Open label facing up, and insert it into the copier slowly until it stops. 0 7// Figure 1-416 4) Peel the end of the Open seal of the cartridge, and pull it horizontally with the warning ...label facing up; Figure 1-417 Figure 1-419 COPYRIGHT © 1994 CANON INC. CANON PCT20/7401150M0 RE© AUG.1994 PRINTEDIN JAPAN twat AUJAPON) 1 - 17 Figure 1-418 6) Press down on the mark on the copier's top to close the body. GENERAL DESCRIPTION 3) Take out the new cartridge from its...
then, rotate it about 90° several times. 5) Hold the cartridge with the Open label facing up, and insert it into the copier slowly until it stops. 0 7// Figure 1-416 4) Peel the end of the Open seal of the cartridge, and pull it horizontally with the warning ...label facing up; Figure 1-417 Figure 1-419 COPYRIGHT © 1994 CANON INC. CANON PCT20/7401150M0 RE© AUG.1994 PRINTEDIN JAPAN twat AUJAPON) 1 - 17 Figure 1-418 6) Press down on the mark on the copier's top to close the body. GENERAL DESCRIPTION 3) Take out the new cartridge from its...
Service Manual
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... MI I. Image exposure) (7. Separation Registration : Flow of copy paper (Cassette/manual feed) : Rotation of photosensitive drum Figure 2-102 COPYRIGHT © t994 CANON INC. IMAGE FORMATION A. Fixing 4. Drum cleaning (3. Outline The copier uses a direct charging/transfer system with each component block arranged as shown in Figure 2-101. /7 7/ 7/ 7/ 7/ + /7 /7 Z Scanning lamp Copyboard glass Lens array...
... MI I. Image exposure) (7. Separation Registration : Flow of copy paper (Cassette/manual feed) : Rotation of photosensitive drum Figure 2-102 COPYRIGHT © t994 CANON INC. IMAGE FORMATION A. Fixing 4. Drum cleaning (3. Outline The copier uses a direct charging/transfer system with each component block arranged as shown in Figure 2-101. /7 7/ 7/ 7/ 7/ + /7 /7 Z Scanning lamp Copyboard glass Lens array...
Service Manual
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... layer made of organic photoconductor (OPC) and inner layer, a substrate made of tow steps: primary charging and image exposure. CANON PC7201140750= REV.O AUG.1994 PRINTED IN JAPAN (IMPRIME AU JAPON) Static Latent Image Formation Block The static latent image formation block...Surface potential (V) -.r------ -1000 Primary charging (step 1) Dark area Image exposure (step 2) Figure 2-104 2 - 2 COPYRIGHT 1994 CANON INC. INN COPYING PROCESS The copier's image formation block consists of the original are called static latent images. At the end of this block, the areas on the...
... layer made of organic photoconductor (OPC) and inner layer, a substrate made of tow steps: primary charging and image exposure. CANON PC7201140750= REV.O AUG.1994 PRINTED IN JAPAN (IMPRIME AU JAPON) Static Latent Image Formation Block The static latent image formation block...Surface potential (V) -.r------ -1000 Primary charging (step 1) Dark area Image exposure (step 2) Figure 2-104 2 - 2 COPYRIGHT 1994 CANON INC. INN COPYING PROCESS The copier's image formation block consists of the original are called static latent images. At the end of this block, the areas on the...
Service Manual
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...charging roller is made of conducting rubber, and an AC bias is charged to a uniform negative potential in the light area. The copier uses its primary charging roller to maintain primary potential. The DC bias applied simultaneously with the AC bias, on the other hand, ...serves to directly charge the photosensitive drum (primary charging). COPYRIGHT © 1994 CANON INC. CANON PC720/740/150M0 REV.O AUG.1994 PRINTED IN JAPAN pmplatt AU JAPON) 2 - 3 Primary Charging (step 1) A-Primary corona roller ti AC bias ...
...charging roller is made of conducting rubber, and an AC bias is charged to a uniform negative potential in the light area. The copier uses its primary charging roller to maintain primary potential. The DC bias applied simultaneously with the AC bias, on the other hand, ...serves to directly charge the photosensitive drum (primary charging). COPYRIGHT © 1994 CANON INC. CANON PC720/740/150M0 REV.O AUG.1994 PRINTED IN JAPAN pmplatt AU JAPON) 2 - 3 Primary Charging (step 1) A-Primary corona roller ti AC bias ...
Service Manual
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... Developing cylinder Toner 0 Cylinder}Developing Magnet cylinder ... DC bias Positive component Negative component Figure 2-109 2 - 4 COPYRIGHT © 1994 CANON INC. The toner has insulating characteristics and becomes positively charged by the friction between the rotating developing cylinder and a blade, where it .... The depositing roller collects toner around it is greater than the positive component. The copier's toner is called developing bias. For this reason, the negative component of the developing bias is charged to scrape residual...
... Developing cylinder Toner 0 Cylinder}Developing Magnet cylinder ... DC bias Positive component Negative component Figure 2-109 2 - 4 COPYRIGHT © 1994 CANON INC. The toner has insulating characteristics and becomes positively charged by the friction between the rotating developing cylinder and a blade, where it .... The depositing roller collects toner around it is greater than the positive component. The copier's toner is called developing bias. For this reason, the negative component of the developing bias is charged to scrape residual...
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...density and the degree of a jam or the like. The copier turns the transfer voltage to positive during post rotation to return the positively charged toner adhering to the transfer roller to the copy paper. The copier uses a roller transfer system, which has the following advantages ...when compared with an increased tendency toward fog- ging. CANON PC7201740/750,710 REV.0 AUG.1994 PRINTED IN JAPAN ompnimt AU JAPON) 2 - 5...
...density and the degree of a jam or the like. The copier turns the transfer voltage to positive during post rotation to return the positively charged toner adhering to the transfer roller to the copy paper. The copier uses a roller transfer system, which has the following advantages ...when compared with an increased tendency toward fog- ging. CANON PC7201740/750,710 REV.0 AUG.1994 PRINTED IN JAPAN ompnimt AU JAPON) 2 - 5...
Service Manual
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...paper, however, has low rigidity and can wrap around the photosensitive drum. To prevent such a problem, the copier applies a positive voltage to the separation static eliminator to a specific temperature. 2 - 6 COPYRIGHT © 1994 CANON INC. The fixing heater is fixed to the film-this design eliminates the need for warm-up time... Figure 2-112 Copy paper is controlled to weaken the static attraction between the photosensitive drum and copy paper, thereby facilitating separation. CANON PC720,740/750i770 REY.0 AUG.1994 PRINTEDIN JAPAN DIARIME AU JAPON) MI COPYING PROCESS G.
...paper, however, has low rigidity and can wrap around the photosensitive drum. To prevent such a problem, the copier applies a positive voltage to the separation static eliminator to a specific temperature. 2 - 6 COPYRIGHT © 1994 CANON INC. The fixing heater is fixed to the film-this design eliminates the need for warm-up time... Figure 2-112 Copy paper is controlled to weaken the static attraction between the photosensitive drum and copy paper, thereby facilitating separation. CANON PC720,740/750i770 REY.0 AUG.1994 PRINTEDIN JAPAN DIARIME AU JAPON) MI COPYING PROCESS G.
Service Manual
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... switching solenoid (PC750/770) Side blank exposure lamp Power switch 00 M2 Scanner/lens drive motor Figure 3-102 3- 2 COPYRIGHT © 1994 CANONINC. Electrical Circuitry The copier's major electrical control mechanisms are driven by the microprocessor on the DC controller PCB. CANON PC72017050/770 REV.O AUG.1994 PRINTEDIN JAPANRout AU JAPON)
... switching solenoid (PC750/770) Side blank exposure lamp Power switch 00 M2 Scanner/lens drive motor Figure 3-102 3- 2 COPYRIGHT © 1994 CANONINC. Electrical Circuitry The copier's major electrical control mechanisms are driven by the microprocessor on the DC controller PCB. CANON PC72017050/770 REV.O AUG.1994 PRINTEDIN JAPANRout AU JAPON)
Service Manual
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... roller Q101 Microprocessor DC controller PCB fluorescent lamp driver High-voltage circuit 4 O900 Microprocessor Composite power supply PCB Figure 3-301 COPYRIGHT 1994 CANON INC. IMAGE FORMATION SYSTEM A. Outline The copier's image formation system performs the following functions: • controls the scanning lamp. • controls the primary/transfer corona current. • controls the...
... roller Q101 Microprocessor DC controller PCB fluorescent lamp driver High-voltage circuit 4 O900 Microprocessor Composite power supply PCB Figure 3-301 COPYRIGHT 1994 CANON INC. IMAGE FORMATION SYSTEM A. Outline The copier's image formation system performs the following functions: • controls the scanning lamp. • controls the primary/transfer corona current. • controls the...
Service Manual
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...temperature is a fluorescent lamp. OPERATIONS AND TIMING= C. trols the scanning lamp (fluorescent lamp; The copier's scanning lamp is low. Scanning lamp Intensity sensor PCB ""At'Ar- •- CANON PC720t740R50/770 REV.O AUG.1994 PRINTED IN JAPAN fMPRIME AU JAPAN) 3- 19 In consideration of ... FLPRHT DC controller PCB Composite power supply PCB Figure 3-304 COPYRIGHT © 1994 CANON INC. The copier does not start copying operation until the intensity of the fluorescent lamp, the copier is turned on and off the scanning lamp. • controls the intensity of the...
...temperature is a fluorescent lamp. OPERATIONS AND TIMING= C. trols the scanning lamp (fluorescent lamp; The copier's scanning lamp is low. Scanning lamp Intensity sensor PCB ""At'Ar- •- CANON PC720t740R50/770 REV.O AUG.1994 PRINTED IN JAPAN fMPRIME AU JAPAN) 3- 19 In consideration of ... FLPRHT DC controller PCB Composite power supply PCB Figure 3-304 COPYRIGHT © 1994 CANON INC. The copier does not start copying operation until the intensity of the fluorescent lamp, the copier is turned on and off the scanning lamp. • controls the intensity of the...
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...Specific Current The AC bias is supplied to a specific current by the oscillation/amplitude control circuit. Switching the DC Bias Voltage Level The copier switches the level of voltage taken. Controlling the DC Bias to a Specific Voltage The DC bias is switched by the microprocessor on the...Scanning lamp (FL1) Primary charging roller DC bias Primary charging roller AC bias P e-heatn -400V -625V -400V Figure 3-307 COPYRIGHT O 1994 CANON INC. The DC bias voltage is controlled to a specific voltage by the microprocessor on measurements of current taken so as to the DC bias ...
...Specific Current The AC bias is supplied to a specific current by the oscillation/amplitude control circuit. Switching the DC Bias Voltage Level The copier switches the level of voltage taken. Controlling the DC Bias to a Specific Voltage The DC bias is switched by the microprocessor on the...Scanning lamp (FL1) Primary charging roller DC bias Primary charging roller AC bias P e-heatn -400V -625V -400V Figure 3-307 COPYRIGHT O 1994 CANON INC. The DC bias voltage is controlled to a specific voltage by the microprocessor on measurements of current taken so as to the DC bias ...
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Controlling the Voltage Level of the DC Bias to Suit the Copy Density Setting The copier varies the DC bias control signal (DCBPWM) according to the settings shown below to vary the DC component voltage, thereby controlling the copy density. • ... user, selected to the changes in the AE sensor output in the sensitivity of the three settings by changes in automatic mode. 3 - 26 COPYRIGHT @ 1994 CANON INC. MEIOPERATIONS AND TIMING ,,,,,w,:m.k- ;,.onw44.0.. 4. CANON PC72017401750/770 REV.O AUG.19M PRINTEDIN JAPAN pout AU JAPON)
Controlling the Voltage Level of the DC Bias to Suit the Copy Density Setting The copier varies the DC bias control signal (DCBPWM) according to the settings shown below to vary the DC component voltage, thereby controlling the copy density. • ... user, selected to the changes in the AE sensor output in the sensitivity of the three settings by changes in automatic mode. 3 - 26 COPYRIGHT @ 1994 CANON INC. MEIOPERATIONS AND TIMING ,,,,,w,:m.k- ;,.onw44.0.. 4. CANON PC72017401750/770 REV.O AUG.19M PRINTEDIN JAPAN pout AU JAPON)
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...STBY Main motor (M1) Cleaning bias Reference bias (ATVC) Transfer bias sec (approx.) U Figure 3-314 3 - 28 COPYRIGHT © 1994 CANON INC. Outline The copier uses a direct transfer method with a roller. Transfer Bias This bias corresponds to the photosensitive drum. • during last rotation.... CANON PC720/74000770 REV.O AUG.1994 PRINTED IN JAPAN pmpFeat AU JAPAN) The transfer ATVC bias is a bias applied each : a. ...
...STBY Main motor (M1) Cleaning bias Reference bias (ATVC) Transfer bias sec (approx.) U Figure 3-314 3 - 28 COPYRIGHT © 1994 CANON INC. Outline The copier uses a direct transfer method with a roller. Transfer Bias This bias corresponds to the photosensitive drum. • during last rotation.... CANON PC720/74000770 REV.O AUG.1994 PRINTED IN JAPAN pmpFeat AU JAPAN) The transfer ATVC bias is a bias applied each : a. ...
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... control signal so that the voltage will be applied to the microprocessor in the transfer effi- This control is pressed, the copier feeds a specific current to the microprocessor on the DC controller PCB sends the transfer bias switching timing signal to the transfer ...in any of copy paper. The current detection circuit detects the current flowing through the transformer/rectifier circuit. 3 - 30 COPYRIGHT © 1994 CANON CANON PC72011401150= RBA AUG.1994 PRINTED IN JAPAN (IMPRNE AU JAPONI Controlling the Transfer Bias to a Specific Voltage The transfer bias is sent to ...
... control signal so that the voltage will be applied to the microprocessor in the transfer effi- This control is pressed, the copier feeds a specific current to the microprocessor on the DC controller PCB sends the transfer bias switching timing signal to the transfer ...in any of copy paper. The current detection circuit detects the current flowing through the transformer/rectifier circuit. 3 - 30 COPYRIGHT © 1994 CANON CANON PC72011401150= RBA AUG.1994 PRINTED IN JAPAN (IMPRNE AU JAPONI Controlling the Transfer Bias to a Specific Voltage The transfer bias is sent to ...