Service Manual
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...) - Copying speed (cpm) 8 10 10 12 COPYRIGHT © 1994 CANON INC. The PC720, PC740, PC750, and PC770 differ from time to time to reflect improvements rendered to the copier; INTRODUCTION This Service Manual contains the basic facts and figures about the plain paper..." deals with the inner workings of the copier associated with the generation of replacement parts and consumables. In CHAPTER 4, "MECHANICAL SYSTEM," the copier's mechanical system is discussed as a handy reference for servicing the machine in the field. CANON PC720174017501770 REV.0 AUG. 1994 PRINTED IN JAPAN...
...) - Copying speed (cpm) 8 10 10 12 COPYRIGHT © 1994 CANON INC. The PC720, PC740, PC750, and PC770 differ from time to time to reflect improvements rendered to the copier; INTRODUCTION This Service Manual contains the basic facts and figures about the plain paper..." deals with the inner workings of the copier associated with the generation of replacement parts and consumables. In CHAPTER 4, "MECHANICAL SYSTEM," the copier's mechanical system is discussed as a handy reference for servicing the machine in the field. CANON PC720174017501770 REV.0 AUG. 1994 PRINTED IN JAPAN...
Service Manual
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NAMES OF PARTS 1-6 1-2 IV. EXPOSURE SYSTEM 3-11 VII. SELF DIAGNOSIS 3-71 V. FIXING SYSTEM 4-30 IV. CANON PC7201740,11501170 REV.O AUG. 1994 PRINTED IN JAPAN (IMPRIME AU JAPON) OPERATIONS 1-8 CHAPTER 2 COPYING PROCESS I ....CHAPTER 5 INSTALLATION I . AUXILIARY PROCESS 2-8 CHAPTER 3 OPERATIONS AND TIMING I . BASIC OPERATION 3-1 VI. IMAGE FORMATION 2-1 II. RELOCATING THE COPIER 5-7 5-2 COPYRIGHT © 1994 CANON INC. PICK-UP/FEEDING SYSTEM 3-36 VIII. SELECTING THE SITE II. FEATURES II. SPECIFICATIONS 1-1 III. EXPOSURE SYSTEM 4-26 VII. FAN 3-...
NAMES OF PARTS 1-6 1-2 IV. EXPOSURE SYSTEM 3-11 VII. SELF DIAGNOSIS 3-71 V. FIXING SYSTEM 4-30 IV. CANON PC7201740,11501170 REV.O AUG. 1994 PRINTED IN JAPAN (IMPRIME AU JAPON) OPERATIONS 1-8 CHAPTER 2 COPYING PROCESS I ....CHAPTER 5 INSTALLATION I . AUXILIARY PROCESS 2-8 CHAPTER 3 OPERATIONS AND TIMING I . BASIC OPERATION 3-1 VI. IMAGE FORMATION 2-1 II. RELOCATING THE COPIER 5-7 5-2 COPYRIGHT © 1994 CANON INC. PICK-UP/FEEDING SYSTEM 3-36 VIII. SELECTING THE SITE II. FEATURES II. SPECIFICATIONS 1-1 III. EXPOSURE SYSTEM 4-26 VII. FAN 3-...
Service Manual
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... paper of existing machines) 3. Uses a SURF fixing assembly. • The use of a charging roller helps to ensure stable copy images. 5. CANON PC7201740/7501770 REV.0 AUG.1994 PRINTED IN JAPAN fMPRIME AU JAPAN) 1 - 1 Integrated cartridge for the environment. • The use of ozone;...black toner cartridge may be opened to 1/000 of sizes between 70% and 141% may be selected. 2. COPYRIGHT @ 1994 CANON INC. Separate top unit. • The copier's top unit may be given an extra finish. 7. I. GENERAL DESCRIPTION - average of 0.01 ppm or less, maximum of...
... paper of existing machines) 3. Uses a SURF fixing assembly. • The use of a charging roller helps to ensure stable copy images. 5. CANON PC7201740/7501770 REV.0 AUG.1994 PRINTED IN JAPAN fMPRIME AU JAPAN) 1 - 1 Integrated cartridge for the environment. • The use of ozone;...black toner cartridge may be opened to 1/000 of sizes between 70% and 141% may be selected. 2. COPYRIGHT @ 1994 CANON INC. Separate top unit. • The copier's top unit may be given an extra finish. 7. I. GENERAL DESCRIPTION - average of 0.01 ppm or less, maximum of...
Service Manual
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...single transparency on the singlefeeder. • You must not set the ratio between 70% and 141% in 1% increments. COPYRIGHT © 1994 CANON INC. a. CANON PC72017407501770 REV.0 AUG.1994 PRINTED IN JAPAN (IMPRIME AU JAPON) 1 - 11 open the top unit. (The power turns off mechanism becomes... activated if the copier is finished before the next one transparency on the singlefeeder. 6) Select the multifeeder using the Paper Select...
...single transparency on the singlefeeder. • You must not set the ratio between 70% and 141% in 1% increments. COPYRIGHT © 1994 CANON INC. a. CANON PC72017407501770 REV.0 AUG.1994 PRINTED IN JAPAN (IMPRIME AU JAPON) 1 - 11 open the top unit. (The power turns off mechanism becomes... activated if the copier is finished before the next one transparency on the singlefeeder. 6) Select the multifeeder using the Paper Select...
Service Manual
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.... Remove it if any jam from the cassette, put the sheets in order, and set the stack back in the cassette, go off, and the copier will make the remaining number of the multifeeder. 2) Open the right cover, and check if there is a jam. Figure 1-410 4) Pull out any . ...Removing Jams The Jam indicator flashes to open /close lever to indicate the presence of paper if it . CANON PC720/T401759/770 REV.O AUG.1994 PRINTEDIN JAPANRout AU JAPONI 1 - 15 CI The 'P' indication should go through the following conditions: C) When the cassette has run...
.... Remove it if any jam from the cassette, put the sheets in order, and set the stack back in the cassette, go off, and the copier will make the remaining number of the multifeeder. 2) Open the right cover, and check if there is a jam. Figure 1-410 4) Pull out any . ...Removing Jams The Jam indicator flashes to open /close lever to indicate the presence of paper if it . CANON PC720/T401759/770 REV.O AUG.1994 PRINTEDIN JAPANRout AU JAPONI 1 - 15 CI The 'P' indication should go through the following conditions: C) When the cassette has run...
Service Manual
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...returned to normal, • Advise the user that, although he/she may continue to have white lines or white spots; A.1.•. :anon copier. CANON PC720840r/501770 REV.OAUG.1994 PRINTEDIN JAPAN0MPRIMEAU JAPON) to ensure sal( in order to the instructions under "2. b. Replacing the Cartridge 1) Shift ...up the open/close lever to run out of .lre copier, its capabili• ng this manua ACAUTIO - : In this manii' procedure AGES with this ME 'ith its tun 1. MIGENERAL DESCRIPTION E. When...
...returned to normal, • Advise the user that, although he/she may continue to have white lines or white spots; A.1.•. :anon copier. CANON PC720840r/501770 REV.OAUG.1994 PRINTEDIN JAPAN0MPRIMEAU JAPON) to ensure sal( in order to the instructions under "2. b. Replacing the Cartridge 1) Shift ...up the open/close lever to run out of .lre copier, its capabili• ng this manua ACAUTIO - : In this manii' procedure AGES with this ME 'ith its tun 1. MIGENERAL DESCRIPTION E. When...
Service Manual
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... 1-418 6) Press down on the mark on the copier's top to close the body. CANON PCT20/7401150M0 RE© AUG.1994 PRINTEDIN JAPAN twat AUJAPON) 1 - 17 then, rotate it about 50 cm). Figure 1-417 Figure 1-419 COPYRIGHT © 1994 CANON INC. GENERAL DESCRIPTION 3) Take out the new cartridge from... its bag, and hold it straight out toward the front (about 90° several times. 5) Hold the cartridge with the warning label facing up , and insert it into the copier slowly until it stops. 0 ...
... 1-418 6) Press down on the mark on the copier's top to close the body. CANON PCT20/7401150M0 RE© AUG.1994 PRINTEDIN JAPAN twat AUJAPON) 1 - 17 then, rotate it about 50 cm). Figure 1-417 Figure 1-419 COPYRIGHT © 1994 CANON INC. GENERAL DESCRIPTION 3) Take out the new cartridge from... its bag, and hold it straight out toward the front (about 90° several times. 5) Hold the cartridge with the warning label facing up , and insert it into the copier slowly until it stops. 0 ...
Service Manual
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IMAGE FORMATION A. Image exposure) (7. Transfer 5. 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 ... Drum cleaning (3. Fixing 4. Separation Registration : Flow of copy paper (Cassette/manual feed) : Rotation of photosensitive drum Figure 2-102 COPYRIGHT © t994 CANON INC. Development) Delivery 6. COPYING PROCESS MI I. CANON PC7201740R50M0 REV.O AUG.1994 PRINTEDIN JAPAN OMPRIME AU JAPONI 2 - 1 Primary charging) (2.
IMAGE FORMATION A. Image exposure) (7. Transfer 5. 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 ... Drum cleaning (3. Fixing 4. Separation Registration : Flow of copy paper (Cassette/manual feed) : Rotation of photosensitive drum Figure 2-102 COPYRIGHT © t994 CANON INC. Development) Delivery 6. COPYING PROCESS MI I. CANON PC7201740R50M0 REV.O AUG.1994 PRINTEDIN JAPAN OMPRIME AU JAPONI 2 - 1 Primary charging) (2.
Service Manual
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...therefore, are rid of negative charges. These images created by negative charges are not visible to the white areas of aluminum (conductor). CANON PC7201140750= REV.O AUG.1994 PRINTED IN JAPAN (IMPRIME AU JAPON) Time (t) 0 Light area -500 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 tow steps: primary charging and image exposure. see the descriptions for each step given under its ...
...therefore, are rid of negative charges. These images created by negative charges are not visible to the white areas of aluminum (conductor). CANON PC7201140750= REV.O AUG.1994 PRINTED IN JAPAN (IMPRIME AU JAPON) Time (t) 0 Light area -500 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 tow steps: primary charging and image exposure. see the descriptions for each step given under its ...
Service Manual
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... with the AC bias, on the other hand, serves to directly charge the photosensitive drum (primary charging). COPYING PROCESS OM C. The copier uses its primary charging roller to maintain primary potential. CANON PC720/740/150M0 REV.O AUG.1994 PRINTED IN JAPAN pmplatt AU JAPON) 2 - 3 Image Exposure (step 2) Optical image Dark area Light... area. Figure 2-106 In this step, the optical image of the photosensitive drum is projected to the photosensitive drum to a DC bias. COPYRIGHT © 1994 CANON INC.
... with the AC bias, on the other hand, serves to directly charge the photosensitive drum (primary charging). COPYING PROCESS OM C. The copier uses its primary charging roller to maintain primary potential. CANON PC720/740/150M0 REV.O AUG.1994 PRINTED IN JAPAN pmplatt AU JAPON) 2 - 3 Image Exposure (step 2) Optical image Dark area Light... area. Figure 2-106 In this step, the optical image of the photosensitive drum is projected to the photosensitive drum to a DC bias. COPYRIGHT © 1994 CANON INC.
Service Manual
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...by the friction between the rotating developing cylinder and a blade, where it . the resulting bias is greater than the positive component. The copier's toner is moved between the rotating cylinder and the blade. MN COPYING PROCESS E. Development (step 3) Blade Developing cylinder Toner 0 Cylinder... thin, uniform layer. The developing cylinder receives both black and color) made mostly of the developing bias is called developing bias. CANON PC72N7401150R/0 REV.O AUG.1994 PRINTED IN JAPAN (IMPRIME AU JAPON) For this reason, the negative component of magnetite and resins. DC...
...by the friction between the rotating developing cylinder and a blade, where it . the resulting bias is greater than the positive component. The copier's toner is moved between the rotating cylinder and the blade. MN COPYING PROCESS E. Development (step 3) Blade Developing cylinder Toner 0 Cylinder... thin, uniform layer. The developing cylinder receives both black and color) made mostly of the developing bias is called developing bias. CANON PC72N7401150R/0 REV.O AUG.1994 PRINTED IN JAPAN (IMPRIME AU JAPON) For this reason, the negative component of magnetite and resins. DC...
Service Manual
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...: Toner may collect on the transfer roller if the image on the photosensitive drum fails to transfer to the photosensitive drum. The copier turns the transfer voltage to positive during initial rotation, while the scanner is moving in reverse, and during post rotation to return the... the surface of fogging; COPYING PROCESSIM During copying, the toner is attracted to the copy paper. CANON PC7201740/750,710 REV.0 AUG.1994 PRINTED IN JAPAN ompnimt AU JAPON) 2 - 5 The copier uses a roller transfer system, which has the following advantages when compared with an increased tendency toward ...
...: Toner may collect on the transfer roller if the image on the photosensitive drum fails to transfer to the photosensitive drum. The copier turns the transfer voltage to positive during initial rotation, while the scanner is moving in reverse, and during post rotation to return the... the surface of fogging; COPYING PROCESSIM During copying, the toner is attracted to the copy paper. CANON PC7201740/750,710 REV.0 AUG.1994 PRINTED IN JAPAN ompnimt AU JAPON) 2 - 5 The copier uses a roller transfer system, which has the following advantages when compared with an increased tendency toward ...
Service Manual
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...the photosensitive drum. The fixing film has a seamless construction and is made of special material so that the heater is why the copier's fixing assembly does not have a cleaning mechanism. Separation (step 5) H. this is controlled to the paper while the copy paper... drum and copy paper, thereby facilitating separation. The fixing heater is fixed to a specific temperature. 2 - 6 COPYRIGHT © 1994 CANON INC. CANON PC720,740/750i770 REY.0 AUG.1994 PRINTEDIN JAPAN DIARIME AU JAPON) Fixing (step 6) Copy paper O Fixing heater Thermistor Fixing film Toner Static...
...the photosensitive drum. The fixing film has a seamless construction and is made of special material so that the heater is why the copier's fixing assembly does not have a cleaning mechanism. Separation (step 5) H. this is controlled to the paper while the copy paper... drum and copy paper, thereby facilitating separation. The fixing heater is fixed to a specific temperature. 2 - 6 COPYRIGHT © 1994 CANON INC. CANON PC720,740/750i770 REY.0 AUG.1994 PRINTEDIN JAPAN DIARIME AU JAPON) Fixing (step 6) Copy paper O Fixing heater Thermistor Fixing film Toner Static...
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Electrical Circuitry The copier's major electrical control mechanisms are driven by the microprocessor on the DC controller PCB. The microprocessor reads input signals from the sensors and the operation ... to the instructions of the program stored in advance and generates signals used to drive such loads as motors, solenoids, and lamps. =OPERATIONS AND TIMING B. CANON PC72017050/770 REV.O AUG.1994 PRINTEDIN JAPANRout AU JAPON) DC controller PCB Sensor • Scanner home position detection • Lens home position detection • Pre...
Electrical Circuitry The copier's major electrical control mechanisms are driven by the microprocessor on the DC controller PCB. The microprocessor reads input signals from the sensors and the operation ... to the instructions of the program stored in advance and generates signals used to drive such loads as motors, solenoids, and lamps. =OPERATIONS AND TIMING B. CANON PC72017050/770 REV.O AUG.1994 PRINTEDIN JAPANRout AU JAPON) DC controller PCB Sensor • Scanner home position detection • Lens home position detection • Pre...
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. OPERATIONS AND TIMINGISM III. Outline The copier's image formation system performs the following functions: • controls the scanning lamp. • controls the primary/transfer corona current. • controls...
... 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. OPERATIONS AND TIMINGISM III. Outline The copier's image formation system performs the following functions: • controls the scanning lamp. • controls the primary/transfer corona current. • controls...
Service Manual
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...Lamp 1. trols the scanning lamp (fluorescent lamp; Scanning lamp Intensity sensor PCB ""At'Ar- •- CANON PC720t740R50/770 REV.O AUG.1994 PRINTED IN JAPAN fMPRIME AU JAPAN) 3- 19 The copier's scanning lamp is low. moreover, its intensity does not stabilize for some time if its ambient temperature ... that the originals may be illuminated only after the intensity of the fluorescent lamp has been checked and verified that con- The copier does not start copying operation until the intensity of the fluorescent lamp has stabilized. Pre-heat transformer (T401) Pre-heat voltage control...
...Lamp 1. trols the scanning lamp (fluorescent lamp; Scanning lamp Intensity sensor PCB ""At'Ar- •- CANON PC720t740R50/770 REV.O AUG.1994 PRINTED IN JAPAN fMPRIME AU JAPAN) 3- 19 The copier's scanning lamp is low. moreover, its intensity does not stabilize for some time if its ambient temperature ... that the originals may be illuminated only after the intensity of the fluorescent lamp has been checked and verified that con- The copier does not start copying operation until the intensity of the fluorescent lamp has stabilized. Pre-heat transformer (T401) Pre-heat voltage control...
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... 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 microprocessor on the DC controller PCB. The DC bias voltage is controlled to the DC bias switching timing signal sent by varying the...to a specific current by the oscillation/amplitude control circuit. Switching the DC Bias Voltage Level The copier switches the level of current taken so as to whether or not copy images are being formed. CANON PC720/740/750/770 REV.O AUG.1994 PRINTED IN JAPAN omput AU JAPON) 3 - 23...
... 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 microprocessor on the DC controller PCB. The DC bias voltage is controlled to the DC bias switching timing signal sent by varying the...to a specific current by the oscillation/amplitude control circuit. Switching the DC Bias Voltage Level The copier switches the level of current taken so as to whether or not copy images are being formed. CANON PC720/740/750/770 REV.O AUG.1994 PRINTED IN JAPAN omput AU JAPON) 3 - 23...
Service Manual
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... the user, selected to the changes in the AE sensor output in automatic mode. 3 - 26 COPYRIGHT @ 1994 CANON INC. 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... to -580V The density correction switch (SW101) on the DC controller PCB may be set to either of the photosensitive drum. MEIOPERATIONS AND TIMING ,,,,,w,:m.k- ;,.onw44.0.. 4. CANON PC72017401750/770 REV.O AUG.19M PRINTEDIN JAPAN pout AU JAPON)
... the user, selected to the changes in the AE sensor output in automatic mode. 3 - 26 COPYRIGHT @ 1994 CANON INC. 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... to -580V The density correction switch (SW101) on the DC controller PCB may be set to either of the photosensitive drum. MEIOPERATIONS AND TIMING ,,,,,w,:m.k- ;,.onw44.0.. 4. CANON PC72017401750/770 REV.O AUG.19M PRINTEDIN JAPAN pout AU JAPON)
Service Manual
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... voltage at a specific timing to return the toner from the conventional copiers that employ corona charging. To suppress the changes in the copy images caused by changes in the environment or deterio- CANON PC720/74000770 REV.O AUG.1994 PRINTED IN JAPAN pmpFeat AU JAPAN) ...) Cleaning bias Reference bias (ATVC) Transfer bias sec (approx.) U Figure 3-314 3 - 28 COPYRIGHT © 1994 CANON INC. c. Controlling the Transfer Roller Bias 1. Outline The copier uses a direct transfer method with a roller. For this reason, it controls the bias differently from the transfer roller to ...
... voltage at a specific timing to return the toner from the conventional copiers that employ corona charging. To suppress the changes in the copy images caused by changes in the environment or deterio- CANON PC720/74000770 REV.O AUG.1994 PRINTED IN JAPAN pmpFeat AU JAPAN) ...) Cleaning bias Reference bias (ATVC) Transfer bias sec (approx.) U Figure 3-314 3 - 28 COPYRIGHT © 1994 CANON INC. c. Controlling the Transfer Roller Bias 1. Outline The copier uses a direct transfer method with a roller. For this reason, it controls the bias differently from the transfer roller to ...
Service Manual
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... the voltage to be applied to the transfer charging roller 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... the transfer efficiency caused by different types of the following two ways: • before starting copying a. b. After Starting Copying The copier automatically corrects the application voltage during initial rotation after starting copying (ATVC) • after a press on the Copy Start key. The...
... the voltage to be applied to the transfer charging roller 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... the transfer efficiency caused by different types of the following two ways: • before starting copying a. b. After Starting Copying The copier automatically corrects the application voltage during initial rotation after starting copying (ATVC) • after a press on the Copy Start key. The...