JP2016194571A - Image forming apparatus, method of controlling image forming apparatus, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus, a method of controlling the image forming apparatus, and a program with which the occurrence of a failure in cleaning with a first cleaning blade can be suppressed even at the occurrence of paper jam.SOLUTION: A printer 1 comprises photoreceptor drums 31, a conveyance belt 53, photoreceptor blades 36, transfer rollers 54, and a belt cleaner part 55. When the printer detects paper jam and stops printing, a control part 80 switches whether or not to apply a transfer current to the transfer rollers 54 to transfer a part of a toner carried on the photoreceptor drums 31 to the conveyance belt 53, and a toner not transferred remains carried on the photoreceptor drums 31. The toner transferred to the conveyance belt 53 is conveyed to the belt cleaner part 55, and the toner remaining carried on the photoreceptor drums 31 is conveyed to the photoreceptor blades 36.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an image forming apparatus, an image forming apparatus control method, and a program, and more particularly to an image forming apparatus including an apparatus for cleaning a developer remaining on the surface of an image carrier, an image forming apparatus control method, and a program. It is.

  2. Description of the Related Art Conventionally, an electrophotographic image forming apparatus includes a first cleaning blade that removes a primary transfer residual developer from an image carrier, and a second cleaning blade that removes a secondary transfer residual developer from an intermediate transfer member. There is a thing (patent document 1). Japanese Patent Application Laid-Open No. H10-228561 discloses a technique for collecting the developer transferred to the image carrier on both the first cleaning blade and the second cleaning blade. Furthermore, the developer is transferred to the first cleaning blade more than the second cleaning blade until the rotation amount of the image carrier and the intermediate transfer member reaches the predetermined rotation amount with respect to the ratio of the developer transferred to the intermediate transfer member. It is described to do.

JP 2007-47553 A

  By the way, although Patent Document 1 discloses that the developer is shared and collected by both the first cleaning device and the second cleaning device, the first cleaning blade rather than the second cleaning blade is disclosed. If a jam occurs during the time when a large amount of developer is dispensed, there is an increased risk of a cleaning failure occurring in the first cleaning blade.

  The present application has been proposed in view of the above-described problems, and can control the occurrence of a cleaning failure in the first cleaning blade even when a jam occurs, and control of the image forming apparatus. It is an object to provide a method and a program.

  The image forming apparatus according to the present application includes a photosensitive member, a belt in contact with the photosensitive member, a first cleaning blade that contacts the photosensitive member and cleans the developer carried on the photosensitive member, and applies a voltage to the photosensitive member. A transfer unit that transfers the developer carried on the belt to the belt, a belt cleaner that contacts the belt and cleans the developer carried on the belt, and a control unit. A printing process for printing the developer carried on the sheet, a first determination process for determining whether or not a jam has occurred during the printing process, and a jam has occurred during the printing process in the first determination process. Depending on the determination, after executing the print stop process for stopping the print process and the print stop process, the amount of the developer conveyed to the first cleaning blade among the developers carried on the photosensitive member is set. Constant processing, first conveyance processing for conveying the amount of developer set by the setting processing to the first cleaning blade to the photosensitive member, and development of the amount set by the setting processing from the developer carried on the photosensitive member And a second transport process for transporting the developer, excluding the developer, to the belt cleaner to the belt cleaner.

  If a jam occurs during the printing process, the developer remains on the photoconductor, and the amount of developer carried on the photoconductor may be large. When a jam occurs, the developer amount set by the setting process is conveyed to the first cleaning blade, and the developer that has not been conveyed to the first cleaning blade is conveyed to the belt cleaner. Thereby, it is possible to suppress a cleaning failure with the first cleaning blade.

  According to the image forming apparatus and the like according to the present application, it is possible to suppress the occurrence of cleaning failure in the first cleaning blade even when a jam occurs.

It is sectional drawing which shows schematic structure of the laser printer of embodiment. It is a block diagram which shows the electric constitution of a laser printer. It is a flowchart which shows the processing content of a printing process. It is the schematic diagram which expanded the part in connection with the photosensitive drum of a laser printer. 5 is a flowchart showing the processing content of a developer amount setting process. It is a flowchart which shows the processing content of a collection process.

  A configuration of a laser printer (hereinafter abbreviated as a printer) 1 according to the present application will be described with reference to FIG. The printer 1 is a so-called tandem laser printer that uses four color toners.

  In the following description, the direction will be described with reference to the user who uses the printer 1. That is, in FIG. 1, the right side is “front”, the left side is “rear”, the front side is “left”, and the back side is “right”. Also, the vertical direction in FIG.

  As shown in FIG. 1, the printer 1 has a substantially box-shaped main body housing 2, and a paper feeding unit 10, an image forming unit 20, and the like are housed inside the main body housing 2. A discharge tray 5 is formed on the upper surface of the main body housing 2, and the discharge tray 5 stores sheets P on which images are formed in a stacked state.

  The sheet feeding unit 10 includes a sheet feeding tray 11 in which sheets P are accommodated, a sheet feeding roller 12, and various rollers. The sheets P are separated one by one by the paper feed roller 12 and fed to the image forming unit 20 by various rollers. The paper feed tray 11 is configured to be detachable from the lower portion of the main body housing 2.

  The image forming unit 20 is disposed at a substantially central portion inside the main body housing 2 and includes process cartridges 30C, 30M, 30Y, and 30K, an exposure unit 40, a transfer unit 50, and a fixing unit 60.

  The process cartridges 30C, 30M, 30Y, and 30K contain cyan, magenta, yellow, and black toners, respectively. The four process cartridges 30C to 30K are provided in the order of the process cartridges 30K, 30Y, 30M, and 30C from the front to the rear of the printer 1. Further, the process cartridges 30C to 30K are detachably installed with the front cover 2a provided in the main body housing 2 opened.

  The process cartridge 30C includes a photosensitive drum 31, a charging roller 32, a toner cartridge 33C, and the like. The other process cartridges 30M, 30Y, and 30K have different toner colors, but the other configurations are the same as those of the process cartridge 30C. For this reason, in the following description, the process cartridge 30C will be described as a representative, and description of the other process cartridges 30M, 30Y, and 30K will be omitted as appropriate.

  The charging roller 32 is disposed in pressure contact with the photosensitive drum 31. The charging roller 32 uniformly positively charges the surface of the photosensitive drum 31 prior to forming an electrostatic latent image on the surface of the photosensitive drum 31 during image formation.

  The toner cartridge 33C has a toner storage chamber 33a, a developing roller 33f, and the like. The toner storage chamber 33a stores cyan toner. The developing roller 33 f is disposed on the downstream side of the charging roller 32 along the rotation direction of the photosensitive drum 31. A positive voltage is applied to the roller shaft of the developing roller 33f. As a result, a potential difference is formed between the developing roller 33 f and the potential of the electrostatic latent image formed on the photosensitive drum 31, and the toner moves to the photosensitive drum 31.

  The exposure unit 40 is disposed at the uppermost position inside the main body housing 2 and includes a laser light source, a polygon mirror, and the like (not shown). The laser beam emitted from the laser light source is deflected by the polygon mirror and applied to the surface of the photosensitive drum 31. Thereby, an electrostatic latent image is formed.

  The transfer unit 50 is disposed above the sheet feeding unit 10 and below the process cartridge 30. The transfer unit 50 forms a color image on the sheet P while conveying the sheet P fed by the sheet feeding unit 10 toward the discharge tray 5. The transfer unit 50 includes a driving roller 51, a driven roller 52, a conveyor belt 53, a plurality of transfer rollers 54, and the like.

  The conveyor belt 53 is an endless belt configured by an annular belt. Between the driving roller 51 positioned below the rear end of the process cartridge 30C and the driven roller 52 positioned below the front end of the process cartridge 30K. It is stretched over.

  Each transfer roller 54 is in contact with the conveyance belt 53 from the back side of the sheet conveyance surface 53A at a position facing each photosensitive drum 31 with the sheet conveyance surface 53A of the conveyance belt 53 interposed therebetween. Each transfer roller 54 transfers a toner image carried on the surface of the photosensitive drum 31 to the sheet P conveyed on the sheet conveyance surface 53A by applying a transfer current at a predetermined timing. The rotation axis direction of the conveyor belt 53 is the main scanning direction. Further, the conveyance direction of the sheet P is the sub-scanning direction.

  The fixing unit 60 is disposed downstream of the transfer unit 50 in the transport direction. The fixing unit 60 includes a heating roller 61 and a pressure roller 62 and fixes the toner image transferred to the sheet P.

  The printer 1 also includes an optical sensor 71, a toner recovery unit 35, and a belt cleaner unit 55.

  Two optical sensors 71 are provided on the lower rear side of the conveyor belt 53, and these two optical sensors 71 are arranged side by side in the left-right direction. Each optical sensor 71 is a reflective sensor including a light emitting element such as an LED and a light receiving element such as a phototransistor. Specifically, the light emitting element irradiates light on the surface of the conveyor belt 53 from an oblique direction, and the light receiving element receives reflected light from the surface of the conveyor belt 53. As a result, the density and position of a known patch formed on the conveyor belt 53 are measured.

  The toner recovery unit 35 is provided on the rear side of each photosensitive drum 31 and below the charging roller 32. The toner recovery unit 35 includes a photoreceptor cleaning blade (hereinafter abbreviated as “photoreceptor blade”) 36, a recovery case 37, and the like. The photoreceptor blade 36 is formed in a substantially flat plate shape, and the surface is covered with a rubber material. The front end portion is fixed in the toner collecting portion 35 so as to be in sliding contact with the surface of the photosensitive drum 31. The collection case 37 is formed in a substantially cylindrical shape that is long in the left-right direction, and a portion facing the photosensitive drum 31 is opened. When the photosensitive drum 31 rotates, paper dust, toner, and the like attached to the surface of the photosensitive drum 31 are scraped off by the photosensitive blade 36 and fall into the collection case 37.

  The belt cleaner 55 is disposed below the conveyor belt 53. The belt cleaner 55 includes a cleaning roller 56, a backup roller 56a, a collection roller 57, a belt cleaning blade (hereinafter abbreviated as belt blade) 58, a storage box 59, and the like.

  The cleaning roller 56 is made of a foam material such as silicone that covers the roller shaft and the periphery of the roller shaft. The backup roller 56 a is disposed to face the cleaning roller 56 with the conveyance belt 53 interposed therebetween. The backup roller 56a is made of metal. The cleaning roller 56 is rotationally driven in a direction opposite to the rotation direction of the conveyance belt 53 while being in contact with the conveyance belt 53. The collection roller 57 is made of metal and is in contact with the cleaning roller 56. The belt blade 58 is made of rubber, for example, and is in contact with the collection roller 57.

  The backup roller 56 a is grounded, and a negative voltage is applied to the cleaning roller 56 and the collection roller 57. As a result, a potential difference is generated between the backup roller 56 a and the cleaning roller 56 and between the cleaning roller 56 and the collection roller 57. For example, when positively charged toner remains, the toner moves from the conveyor belt 53 to the cleaning roller 56 by electrostatic force. Further, the potential difference between the cleaning roller 56 and the collection roller 57 is set larger than between the backup roller 56 a and the cleaning roller 56, and the toner moves from the cleaning roller 56 to the collection roller 57. The belt blade 58 scrapes off the toner adhering to the collecting roller 57, and the scraped toner is stored in the storage box 59.

  Next, the operation at the time of image formation in the printer 1 will be described. In the printer 1, the surface of each photosensitive drum 31 is uniformly positively charged by each charging roller 32 and is exposed by the exposure unit 40 based on the print data. Thereby, an electrostatic latent image corresponding to each toner color is formed on the surface of each photosensitive drum 31. Next, the printer 1 supplies toner to the electrostatic latent image formed on the surface of the photosensitive drum 31 by the developing roller 33f. As a result, the electrostatic latent image on the surface of the photosensitive drum 31 is developed, and the printer 1 carries a toner image on the surface of the photosensitive drum 31.

  On the other hand, the printer 1 causes the sheet feeding unit 10 to convey the sheet P to the image forming unit 20 at a predetermined timing. The printer 1 transfers the toner image carried on the surface of the photosensitive drum 31 onto the sheet P by a transfer current applied to the roller shaft of the transfer roller 54. Then, the printer 1 conveys the sheet P to the fixing unit 60 and thermally fixes the toner to the sheet P. Thereafter, the printer 1 causes the sheet P to be discharged to the discharge tray 5 by the discharge roller 65.

  The printer 1 cleans the photosensitive drum 31 that has been transferred to the sheet P by the photosensitive blade 36 to prepare for the next image formation. Further, the printer 1 causes the belt cleaner unit 55 to clean the conveyance belt 53 that has been transferred to the sheet P.

  Next, the electrical configuration of the printer 1 will be described with reference to FIG. The printer 1 includes a control unit 80, a transfer current application circuit 101, a sheet sensor 72, a display operation unit 73, and the like in addition to the paper feeding unit 10 and the image forming unit 20 shown in FIG. The control unit 80 includes a CPU 81, a ROM 82, a RAM 83, a first timer 84, a first counter 87, an NVRAM (nonvolatile RAM) 89, and the like. The CPU 81 executes various programs stored in the ROM 82, whereby the paper feeding unit 10, the image forming unit 20, the transfer current application circuit 101, the optical sensor 71, the sheet sensor 72, and the like connected via the bus 90. And the display operation unit 73 and the like. The ROM 82 stores a control program and various data. The RAM 83 is used as a main storage device for the CPU 81 to execute various processes. The first timer 84 measures an elapsed time after the photosensitive drum 31 and the conveyance belt 53 are rotated. The first counter 87 counts the number of printed sheets after collection processing (described later). The number of printed sheets is a value converted from the number of rotations of the photosensitive drum 31, and is converted as one sheet is printed at every predetermined number of rotations.

  The transfer current application circuit 101 is electrically connected to the roller shaft of the transfer roller 54. The controller 80 controls the transfer current application circuit 101 to control the transfer current applied to the roller shaft of the transfer roller 54. The sheet sensor 72 is for detecting the sheet P being conveyed on the conveyance path R, and a plurality of sheet sensors 72 are provided on the conveyance path R. The sheet sensor 72 includes, for example, an irradiation unit (not shown) that irradiates light to the conveyor belt 53 and a light receiving unit (not shown) that receives reflected light from the conveyor belt 53, and the conveyor belt according to the amount of received light 53 is a photoelectric switch that detects the presence or absence of the sheet P on the sheet 53. The display operation unit 73 includes, for example, a liquid crystal display and a plurality of buttons. The control unit 80 can display a setting screen for printing, the operation state of the printer 1 and the like on the liquid crystal display. In addition, the user can perform various operations by selecting a button or the like displayed on the liquid crystal display.

  Next, print processing according to the embodiment will be described with reference to FIGS. The control unit 80 executes the program stored in the ROM 82 every predetermined time, and starts processing according to the flowcharts shown in FIGS. First, the control unit 80 determines whether or not a print job is received from an external device such as a personal computer via a network (S1). In response to determining that a print job has not been received (S1: NO), the process returns to step S1. On the other hand, in response to determining that the print job has been received (S1: YES), the printing process is started according to the contents of the print job (S3). That is, the control unit 80 starts the operation at the time of image formation described above. At this time, the transfer current application circuit 101 starts application of the transfer current.

  Next, based on the detection signal from the sheet sensor 72, it is determined whether or not a jam has been detected (S5). In response to the detection of the jam (S5: YES), the printing process is stopped (S7). At this time, the control unit 80 causes the transfer current application circuit 101 to stop applying the transfer current. In addition, the charging, exposure, and development operations for the charging roller 32, the exposure unit 40, and the developing roller 33f are stopped, and the rotation of the photosensitive drum 31 and the conveyance belt 53 is stopped. Further, an error message is displayed on the display operation unit 73 to notify the user of the occurrence of a jam. Thus, the user removes the sheet P causing the jam and releases the jam. Next, the control unit 80 determines whether or not an input of jam release completion has been made (S9). Specifically, the control unit 80 causes the display operation unit 73 to display a message “Did you release the jam?” And a selection button “OK”, and release the jam in response to the user selecting the “OK” button. It is determined that there is an input for completion. In response to determining that there is no jam clear completion input (S9: NO), the control unit 80 returns to step S9 and waits for a jam clear completion input. On the other hand, the developer amount setting process (S11) is executed in response to determining that there has been an input of jam release completion (S9: YES).

  By the way, when printing is stopped in step S7, the toner is still carried on the photosensitive drum 31. This will be described in detail with reference to FIG. The surface of each photosensitive drum 31 is charged by the charging roller 32 and then exposed by the exposure unit 40. Next, toner is supplied to the surface of the photosensitive drum 31 by the developing roller 33f. If printing is stopped in step S7, the sheet P is not conveyed, so the processing is stopped here. Accordingly, the toner remains on the photosensitive drum 31. There may be a case where a larger amount of toner is carried on the surface of the photosensitive drum 31 as compared with a state where the transfer to the sheet P has been completed.

  When the amount of toner remaining on the photosensitive drum 31 is large, when all of the toner is conveyed to the photosensitive blade 36, for example, between the tip of the photosensitive blade 36 and the surface of the photosensitive drum 31. An external additive such as silica may be sandwiched, and a gap may be formed between the tip of the photoreceptor blade 36 and the surface of the photoreceptor drum 31. As the toner slips through the gap between the tip of the photoreceptor blade 36 and the surface of the photoreceptor drum 31, toner that is not scraped off by the photoreceptor blade 36 may remain on the surface of the photoreceptor drum 31. That is, there is a risk that a cleaning failure will occur. In particular, when the charging roller 32 is provided, since the charging roller 32 is in contact with the photosensitive drum 31, the charging roller 32 is contaminated by toner remaining on the photosensitive drum 31, for example, the ability to charge the photosensitive drum 31 is reduced. It is easy for problems to occur. Therefore, in the recovery process (described later), an amount of toner that can be recovered satisfactorily by the photoreceptor blade 36 is retained on the photoreceptor drum 31 and is collected by the photoreceptor blade 36, and the remaining toner is transferred to the conveyance belt 53. By causing the belt cleaner 55 to collect the toner, the defective cleaning of the photosensitive blade 36 is suppressed. The toner image formed in the range from the development position 110 to the transfer position 111 on the surface of the photosensitive drum 31 is hereinafter referred to as residual toner T.

  In the collection process described later, the residual toner T is distributed to both the photosensitive blade 36 and the belt cleaner 55. Here, by switching whether the transfer current is applied to the transfer roller 54 or not, it is controlled whether the residual toner T is transferred to the conveyance belt 53 or is held on the photosensitive drum 31. The toner transferred to the conveyance belt 53 is collected by the belt cleaner 55, and the toner carried on the photosensitive drum 31 is collected by the photosensitive blade 36.

  A developer amount setting process executed by the control unit 80 in order to determine the amount of toner to be transferred to the conveyance belt 53 prior to the collection process will be described with reference to FIG.

  First, the control unit 80 reads the number of printed sheets from the previous collection process from the first counter 87 (S31), and determines whether or not the number is larger than a predetermined number (S33). When it is determined that the number of printed sheets from the previous collecting process is larger than the predetermined number (S33: YES), the non-transfer time is stored as time A in the NVRAM 89 (S35), and the process is terminated. On the other hand, in response to determining that the number of printed sheets from the previous collection process is less than the predetermined number (S33: NO), the non-transfer time is stored in NVRAM 89 as time B shorter than time A (S37), and the process is terminated. To do. Here, the non-transfer time is a set value used in the next recovery process, and is a time for rotating the photosensitive drum 31 and the conveyance belt 53 without applying a transfer current. While the non-transfer time elapses, the residual toner T carried on the photosensitive drum 31 passes through the transfer position 111 without being transferred and remains carried on the photosensitive drum 31. That is, the amount of toner collected by the photoreceptor blade 36 is determined by the non-transfer time. The time A is a time that does not exceed the maximum amount of toner that can be collected by the photoconductor blade 36, and is a time determined by experiment, for example. Further, when the collection process is executed, toner accumulates on the photosensitive blade 36, but when the print process is executed, the toner is gradually lost. Therefore, when it is determined that the number of printed sheets from the previous collection process is not more than the predetermined number (S33: NO), the toner is accumulated on the photosensitive blade 36, and therefore excessive toner is supplied. May cause a cleaning failure. Therefore, by setting the non-transfer time to a time B shorter than the time A, the occurrence of defective cleaning is suppressed.

  Next, the collection process (S13) to be executed will be described with reference to FIG. The controller 80 starts the rotation of the photosensitive drum 31 and the conveyance belt 53 (S41). Next, the non-transfer time which is the time A or B stored in the NVRAM 89 is read, and it is determined whether or not the non-transfer time has elapsed since the start of rotation (S43). If it is determined that the non-transfer time has not elapsed (S43: NO), the process returns to step S43 and waits until the non-transfer time has elapsed. On the other hand, in response to determining that the non-transfer time has elapsed (S43: YES), the transfer current applying circuit 101 is applied with a transfer current (S45). Next, the elapsed time is read from the first timer 84, and the time required for the fixed point on the surface of the photosensitive drum 31 to reach the transfer position 111 after passing through the development position 110 (hereinafter referred to as transfer position arrival time). It is determined whether the photosensitive drum 31 has been rotated (S47). When it is determined that the photosensitive drum 31 is not rotated during the transfer position arrival time (S47: NO), the process waits until the transfer position arrival time elapses. On the other hand, when it is determined that the photosensitive drum 31 has been rotated during the transfer position arrival time (S47: YES), it is determined that all of the residual toner T has passed the transfer position 111. The application of the transfer current is stopped (S49), and the process ends. Note that the control unit 80 resets the first counter 87 at the end of the collection process.

  The controller 80 rotates the photosensitive drum 31 so that the toner carried on the photosensitive drum 31 is collected by the photosensitive blade 36 after passing through the transfer position 111. Further, the control unit 80 causes the belt cleaner unit 55 to collect the toner transferred to the conveyance belt 53 by rotating the conveyance belt 53.

  Returning to FIG. 3, the description of the printing process will be continued. After the collection process (S13), the control unit 80 determines whether or not the conveyor belt 53 has been rotated two or more times (S15). In response to determining that the conveying belt 53 has not been rotated two or more times (S15: NO), the process returns to step S15 and waits until the conveying belt 53 is rotated two or more times. On the other hand, in response to determining that the conveying belt 53 has been rotated two or more times (S15: YES), since it is determined that all the toner transferred to the conveying belt 53 has been collected, the processing ends. Specifically, the control unit 80 determines whether or not a portion of the conveyance belt 53 to which the toner has been transferred has passed a time equivalent to passing twice through the position between the cleaning roller 56 and the backup roller 56a. Determine whether. As a result, even if there is a large amount of toner transferred to the conveyor belt 53 and the toner cannot be recovered by passing the belt cleaner 55 once, it is transferred to the conveyor belt 53 by passing multiple times. The collected toner can be recovered.

  On the other hand, when the jam is not detected (S5: NO), the control unit 80 determines whether or not printing of one sheet is completed (S17). When it is determined that printing of one sheet is completed (S17: YES), the first counter 87 is incremented by 1 (S19), and it is determined whether or not the print job is completed (S21). When it is determined that the print job has been completed (S21: YES), the process is terminated. On the other hand, when it is determined that the printing of one sheet is not completed (S17: NO) and when it is determined that the print job is not completed (S21: NO), the process returns to step S5.

  Here, the photosensitive drum 31 is an example of a photosensitive member, and the conveyance belt 53 is an example of a belt. The photoreceptor blade 36 is an example of a first cleaning blade, and the belt cleaner 55 is an example of a belt cleaner and a developer recovery device. The belt blade 58 is an example of a second cleaning blade, and the storage box 59 is an example of a storage unit. Step S51 is an example of the first determination process, step S7 is an example of the print stop process, the developer amount setting process (S11) is an example of the setting process, and the collection process (S13) is an example of the transport process. is there. Steps S41 and S43 are an example of the first transport process, and steps S45 and S47 are an example of the second transport process. Step S19 is an example of a counting process, and step S33 is an example of a second determination process. Toner is an example of a developer.

As mentioned above, according to above-mentioned embodiment, there exist the following effects.
When a jam occurs (S5: YES), a large amount of toner may be held on the photosensitive drum 31 in some cases. Also in this case, the toner amount set by the developer amount setting process (S11) is conveyed to the photosensitive blade 36, and the toner that has not been conveyed to the photosensitive blade 36 is conveyed to the belt cleaner 55. Thereby, it is possible to suppress a cleaning failure in the photosensitive member blade 36.

  Further, the control unit 80 switches whether to apply a transfer current to the transfer roller 54 so that the toner carried on the photosensitive drum 31 is transferred to the conveying belt 53 or not transferred to the photosensitive drum 31 without being transferred. Control whether to keep it supported. As a method of distributing the toner carried on the photosensitive drum 31 to the photosensitive drum 31 and the belt cleaner 55, there is a method of controlling the current value of the transfer current applied by the transfer roller 54. Specifically, by applying a current value smaller than the current value applied in the printing process, a part of the toner carried on the photosensitive drum 31 is transferred to the transport belt 53, and the toner that has not been transferred is exposed to light. It is held on the body drum 31. The amount of toner transferred to the conveyor belt 53 is controlled by controlling the current value. On the other hand, in the method of switching whether or not to apply a transfer current to the transfer roller 54, the amount of toner carried on the photosensitive drum 31 is controlled by switching whether or not current is applied. Occurrence of a cleaning failure in the photoreceptor blade 36 can be suppressed by the magnitude of the current value or the presence or absence of current application. In the method of switching whether or not the transfer current is applied to the transfer roller 54, the amount of toner that is held on the photosensitive drum 31 can be controlled more accurately. It is possible to further expect the effect of suppressing the occurrence of the above.

  Further, after the collection process (S13), the conveyor belt 53 is rotated two or more times. Even when toner that cannot be removed by passing once through the belt cleaner 55 is transferred to the conveyor belt 53, the toner transferred to the conveyor belt 53 is removed by passing through the belt cleaner 55 multiple times. be able to. While suppressing poor cleaning at the belt cleaner 55, after the jam occurs, only the amount that can be satisfactorily recovered by the photosensitive blade 36 from the toner carried on the photosensitive drum 31 is left on the photosensitive drum 31, and the rest is left. The image can be transferred to the conveyance belt 53.

  Further, in the charging roller 32 that comes into contact with the photosensitive drum 31, when the charging roller 32 comes into contact with the photosensitive drum 31 while the toner is carried on the photosensitive drum 31, the charging roller 32 is contaminated with the toner, and the photosensitive member of the charging roller 32. The ability to charge the drum 31 may be reduced. Even when a jam occurs, an amount that can be satisfactorily recovered by the photosensitive drum 31 out of the toner carried on the photosensitive drum 31 is kept carried on the photosensitive drum 31, and the rest is transferred to the conveying belt 53. As a result, the cleaning failure in the photoconductor blade 36 is suppressed. Thereby, it is possible to prevent the charging roller 32 from being contaminated with toner.

  Further, after the collection process (S13) is executed, toner is accumulated on the photosensitive blade 36, and if a large amount of toner is conveyed, there is a possibility that a cleaning failure may occur. In step S33, when it is determined that the number of printed sheets from the previous collection process is not equal to or greater than the predetermined number, the non-transfer time is set shorter than when it is determined that the number of printed sheets is equal to or greater than the predetermined number. As a result, the amount of toner conveyed to the photoreceptor blade 36 is reduced, and the occurrence of defective cleaning in the photoreceptor blade 36 can be suppressed.

  In the developer amount setting process (S11), the non-transfer time is set according to the maximum cleaning capability of the photosensitive blade 36. That is, an amount that does not exceed the maximum amount of toner that can be collected by the photosensitive blade 36 is set to be held on the photosensitive drum 31. Thereby, it is possible to suppress a cleaning failure in the photosensitive member blade 36.

Needless to say, the present invention is not limited to the above-described embodiment, and various improvements and modifications can be made without departing from the spirit of the present invention.
For example, in the embodiment, the method of directly transferring the toner image formed on the photosensitive drum 31 to the sheet P has been described, but the present invention is not limited to this. The toner image formed on the photoconductive drum 31 can also be applied to a so-called secondary transfer type image forming apparatus in which the toner image is once transferred to a belt and further transferred to a sheet P.

  In step S31, it is determined whether the number of printed sheets converted from the number of rotations of the photosensitive drum 31 is equal to or greater than a predetermined number. However, the present invention is not limited to this. It can also be determined by the number of printed sheets converted from the charging time of the charging roller 32 or the like. Alternatively, the rotational speed of the photosensitive drum 31 and the charging time of the charging roller 32 may be compared with a predetermined number and a predetermined time, respectively.

  Further, it has been described that the controller 80 distributes the toner carried on the photosensitive drum 31 to the photosensitive drum 31 and the belt cleaner 55 by switching whether or not to apply a transfer current to the transfer roller 54. However, the present invention is not limited to this, and distribution can be performed by controlling the current value of the transfer current.

  Further, the laser printer 1 has been described as including the charging roller 32, but the present invention is not limited to this. For example, a non-contact charger such as a scorotron type may be provided.

  Further, although it has been described that the transfer current is applied to the roller shaft of the transfer roller 54 by the transfer current application circuit 101, the present invention is not limited to this. A configuration in which a transfer voltage is applied may be employed.

  Further, it has been described that the surface of the photosensitive drum 31 is positively charged by the charging roller 32 and a positive charge is applied to the roller shaft of the developing roller 33f. However, the present invention is not limited to this. The surface of the photosensitive drum 31 may be negatively charged, and a negative charge may be applied to the roller shaft of the developing roller 33f.

  In the embodiment, the laser printer 1 has been described as an example, but the present invention is not limited to this. It may be a so-called multifunction machine having a scanner function, a copy function, a facsimile function, and the like.

  Moreover, although embodiment demonstrated the case where the control part 80 was provided with CPU81 as an example, it is not limited to this. A plurality of CPUs may be provided, or an ASIC may be used. Furthermore, it may be configured by a combination of the CPU 81 and the ASIC.

DESCRIPTION OF SYMBOLS 1 Laser printer 31 Photosensitive drum 32 Charging roller 33f Developing roller 36 Photosensitive blade 50 Transfer part 53 Conveyor belt 54 Transfer roller 55 Belt cleaner part 56 Cleaning roller 58 Belt cleaning blade 59 Storage box 80 Control part 101 Transfer current application circuit P Sheet

Claims (11)

A photoreceptor,
A belt in contact with the photoreceptor;
A first cleaning blade that contacts the photoreceptor and cleans the developer carried on the photoreceptor;
A transfer unit that applies a voltage to transfer the developer carried on the photoconductor to the belt;
A belt cleaner that contacts the belt and cleans the developer carried on the belt;
A control unit;
With
The controller is
A printing process for printing the developer carried on the photoconductor on paper;
A first determination process for determining whether or not a jam has occurred during the printing process;
A print stop process for stopping the print process in response to determining that a jam has occurred during the print process in the first determination process;
A setting process for setting the amount of developer conveyed to the first cleaning blade among the developers carried on the photoconductor after the execution of the printing stop process;
An amount of developer set by the setting process is conveyed to the photoconductor to the first cleaning blade;
Carrying out a carrying process for carrying the developer to the belt cleaner by removing the amount of developer set by the setting process from the developer carried on the photoconductor. An image forming apparatus. The conveyance process is
A first conveyance process in which the photosensitive member and the belt are rotated without applying a voltage to the transfer unit, and an amount of developer set by the setting process is conveyed to the first cleaning blade to the photosensitive member; ,
A voltage is applied to the transfer portion, the photosensitive member and the belt are rotated, and the developer corresponding to the amount of developer set by the setting process is removed from the developer carried on the photosensitive member, The image forming apparatus according to claim 1, further comprising a second conveyance process for conveying the belt to the belt cleaner.   In the second transport process, the control unit rotates the photosensitive member and the belt until a portion of the belt to which the developer has been transferred passes a position where the belt contacts with the belt cleaner more than once. The image forming apparatus according to claim 2.   4. The image forming apparatus according to claim 1, further comprising a charging roller configured to charge the surface of the photosensitive member cleaned by the first cleaning blade. 5. The controller is
A counting process for counting the number of rotations of the photoreceptor;
A second determination process for determining whether or not the number of rotations counted by the counting process after executing the first conveyance process is equal to or greater than a predetermined number of rotations;
Run
In the second determination process, when it is determined that the rotation speed is not equal to or higher than the predetermined rotation speed, the developer conveyed to the first cleaning blade is more than when it is determined that the rotation speed is equal to or higher than the predetermined rotation speed. The image forming apparatus according to claim 1, wherein an amount of the image forming apparatus is reduced.   6. The image forming apparatus according to claim 1, wherein, in the setting process, the developer amount is set in accordance with a maximum cleaning capability of the first cleaning blade. A photoreceptor, a belt in contact with the photoreceptor, a first cleaning blade that contacts the photoreceptor and cleans the developer carried on the photoreceptor, and a voltage is applied to the photoreceptor to carry the photoreceptor. A transfer unit that transfers the developer to the belt, and a belt cleaner that contacts the belt and cleans the developer carried on the belt.
A printing step for printing the developer carried on the photosensitive member on paper;
A first determination step of determining whether or not a jam has occurred during the printing step;
A printing stop step of stopping the printing step in response to determining that a jam has occurred during the printing step in the first determining step;
A setting step for setting the amount of developer conveyed to the first cleaning blade among the developers carried on the photoconductor after execution of the printing stop step;
The developer set in the setting step is transported to the photoconductor to the first cleaning blade,
And a step of transporting the belt to the belt cleaner by the amount of developer obtained by removing the amount of developer set by the setting step from the developer carried on the photoreceptor. Control method for image forming apparatus. A photoreceptor, a belt in contact with the photoreceptor, a first cleaning blade that contacts the photoreceptor and cleans the developer carried on the photoreceptor, and a voltage is applied to the photoreceptor to carry the photoreceptor. A program for controlling an image forming apparatus comprising: a transfer unit that transfers the developer being transferred to the belt; and a belt cleaner that contacts the belt and cleans the developer carried on the belt,
In the image forming apparatus,
A printing process for printing the developer carried on the photoconductor on paper;
A first determination process for determining whether or not a jam has occurred during the printing process;
A print stop process for stopping the print process in response to determining that a jam has occurred during the print process in the first determination process;
A setting process for setting the amount of developer conveyed to the first cleaning blade among the developers carried on the photoconductor after the execution of the printing stop process;
An amount of developer set by the setting process is conveyed to the photoconductor to the first cleaning blade;
A conveying process for conveying the developer to the belt cleaner to the belt cleaner by removing the amount of the developer set by the setting process from the developer carried on the photoreceptor;
A program characterized by having executed. A photoreceptor,
A belt in contact with the photoreceptor;
A first cleaning blade that contacts the photoreceptor and cleans the developer carried on the photoreceptor;
A charging roller for charging the surface of the photoconductor cleaned by the first cleaning blade;
A transfer unit that applies a voltage to transfer the developer carried on the photoconductor to the belt;
A developer recovery container comprising: a roller that contacts the belt; a second cleaning blade that scrapes off the developer recovered by the roller; and a storage portion that stores the developer scraped off by the second cleaning blade. When,
A control unit;
With
The controller is
A printing process for printing the developer carried on the photoconductor on paper;
A first determination process for determining whether or not a jam has occurred during the printing process;
A print stop process for stopping the print process in response to determining that a jam has occurred during the print process in the first determination process;
A setting process for setting the amount of developer conveyed to the first cleaning blade among the developers carried on the photoconductor after the execution of the printing stop process;
Transport the developer in the amount set by the setting process to the first cleaning blade;
Carrying out a carrying process for carrying the developer in a quantity obtained by removing the amount of the developer set by the setting process from the developer carried on the photoconductor to the second cleaning blade. An image forming apparatus. A photoconductor, a belt in contact with the photoconductor, a first cleaning blade that contacts the photoconductor and cleans the developer carried on the photoconductor, and the photoconductor cleaned by the first cleaning blade A charging roller for charging the surface of the toner, a transfer unit for applying a voltage to transfer the developer carried on the photosensitive member to the belt, a roller in contact with the belt, and a roller collected by the roller A control method in an image forming apparatus comprising: a second cleaning blade that scrapes off the developer; and a developer recovery container that includes a storage portion that stores the developer scraped off by the second cleaning blade,
A printing step for printing the developer carried on the photosensitive member on paper;
A first determination step of determining whether or not a jam has occurred during the printing step;
A printing stop step of stopping the printing step in response to determining that a jam has occurred during the printing step in the first determining step;
A setting step for setting the amount of developer conveyed to the first cleaning blade among the developers carried on the photoconductor after execution of the printing stop step;
Transport the amount of developer set in the setting step to the first cleaning blade;
A transporting step for transporting the amount of developer set by the setting step from the developer carried on the photoconductor to the second cleaning blade;
A control method for an image forming apparatus. A photoconductor, a belt in contact with the photoconductor, a first cleaning blade that contacts the photoconductor and cleans the developer carried on the photoconductor, and the photoconductor cleaned by the first cleaning blade A charging roller for charging the surface of the toner, a transfer unit for applying a voltage to transfer the developer carried on the photosensitive member to the belt, a roller in contact with the belt, and a roller collected by the roller A program for controlling an image forming apparatus comprising: a second cleaning blade that scrapes off the developer; and a developer recovery container that includes a storage portion that stores the developer scraped off by the second cleaning blade. ,
In the image forming apparatus,
A printing process for printing the developer carried on the photoconductor on paper;
A first determination process for determining whether or not a jam has occurred during the printing process;
A print stop process for stopping the print process in response to determining that a jam has occurred during the print process in the first determination process;
A setting process for setting the amount of developer conveyed to the first cleaning blade among the developers carried on the photoconductor after the execution of the printing stop process;
Transport the developer in the amount set by the setting process to the first cleaning blade;
A transport process for transporting to the second cleaning blade a developer corresponding to the amount of developer set by the setting process from the developer carried on the photoconductor;
A program characterized by having executed.

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