JP6631140B2 - Image forming apparatus and image forming method - Google Patents

Description

  The present invention relates to an image forming apparatus and an image forming method.

  An electrophotographic image forming apparatus having an intermediate transfer belt, wherein a toner image formed on a photoreceptor is primarily transferred to an intermediate transfer belt, and then secondarily transferred from the intermediate transfer belt to a recording medium. It has been known.

  In the image forming apparatus having the above-described configuration, when a jam occurs, the toner image formed on the intermediate transfer belt is not secondarily transferred to the recording medium, and the recording medium remaining in the apparatus is moved to the jam processing position. (For example, see Patent Document 1). When a jam occurs, the recording medium is collected in a blank state without transferring the toner image, so that the user can perform the jam processing without soiling the hands with the toner on the recording medium.

  In the method according to Patent Document 1, untransferred toner remaining on the secondary transfer belt when a jam occurs is collected by a cleaning unit provided around the secondary transfer belt. Here, when printing with a high image area ratio is large and jams occur frequently, the amount of untransferred toner exceeds the recovery capacity of the cleaning unit, and the toner may overflow from the cleaning unit and contaminate the inside of the apparatus. Further, the recording medium may be stained by toner dropped from the cleaning unit during printing, and printing failure may occur.

  The present invention has been made in view of the above, and has as its object to provide an image forming apparatus capable of reducing a toner collection load of a cleaning unit provided on an intermediate transfer member when a jam occurs.

According to the image forming apparatus of one aspect of the present invention, an image forming unit that forms a toner image on an intermediate transfer body, and is arranged at a secondary transfer position between the intermediate transfer body and the second transfer position between the intermediate transfer body A transfer unit for secondary-transferring the toner image to a medium, a first cleaning unit for collecting toner remaining on the intermediate transfer body, a second cleaning unit for collecting toner attached to the transfer unit, and a recording medium. Conveying means for conveying along the conveying path, consolidating means provided downstream of the secondary transfer position in the conveying path and consolidating a plurality of recording media, and jamming of the recording medium conveyed on the conveying path And a jam processing unit that controls the transfer unit and the transport unit to execute a jam process when a jam is detected by the jam detection unit. , When the untransferred toner is present the jam is detected on the intermediate transfer body, after the were collected untransferred toner in the cleaning means is transferred to said transfer means from said intermediate transfer member, the 2 The recording medium existing upstream of the next transfer position is conveyed to the collecting unit .

  According to the embodiment of the present invention, there is provided an image forming apparatus capable of reducing a toner collecting load of a cleaning unit provided on an intermediate transfer member when a jam occurs.

FIG. 1 is a diagram illustrating a schematic configuration of an image forming apparatus according to an embodiment. FIG. 2 is a diagram illustrating a schematic configuration of a transport belt in the embodiment. FIG. 5 is a diagram illustrating the operation of the transport belt according to the embodiment. FIG. 4 is a diagram illustrating a state where sheets are collected on a conveyance belt according to the embodiment. It is a figure which shows the modification of a conveyance belt. FIG. 2 is a block diagram illustrating a functional configuration of the image forming apparatus according to the embodiment. FIG. 4 is a diagram illustrating a flowchart of a jam process according to the first embodiment. FIG. 2 is a diagram illustrating a state of the image forming apparatus after the jam processing according to the first exemplary embodiment. FIG. 9 is a diagram illustrating a flowchart of a jam process according to a second embodiment. FIG. 13 is a diagram illustrating a flowchart of a jam process according to a third embodiment.

  Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and redundant description may be omitted.

<Configuration of Image Forming Apparatus>
FIG. 1 is a diagram illustrating a schematic configuration of an image forming apparatus 100 according to the embodiment.

  The image forming apparatus 100 includes photoconductors 700Y, 700M, 700C, and 700K, an intermediate transfer belt 600 as an intermediate transfer body, a secondary transfer roller 601 as a transfer unit, and a fixing device 800. Form a full-color image.

  A charging device (not shown), an optical writing device, a developing device, and the like are provided around each photoconductor 700. Yellow (Y), magenta (M), cyan (C), and black (K) toner images are formed on the surface of each photoconductor 700 that is rotationally driven. The toner images formed on the respective photoconductors 700 are primary-transferred onto the intermediate transfer belt 600 that is rotationally driven by the primary transfer roller 500, and become full-color toner images.

  The toner image formed on the intermediate transfer belt 600 is secondarily transferred to the sheet P by the secondary transfer roller 601 at a secondary transfer position between the intermediate transfer belt 600 and the secondary transfer roller 601.

  The paper P is fed from a paper feed tray 201 or a paper feed tray 202 and is transported along a transport path 210 by a plurality of transport rollers 200 as transport means. The sheet P conveyed along the conveyance path 210 is conveyed to the secondary transfer position by the registration roller 302 in synchronization with the secondary transfer timing of the full-color toner image on the intermediate transfer belt 600.

  For example, as shown in FIG. 1, when images are continuously formed on seven sheets P1 to P7, first, sheets P1 to P7 fed from sheet feed trays 201 and 202 are transported by transport rollers 200 Are sequentially transported along the transport path 210.

  The toner images formed on the respective photoconductors 700 are primarily transferred to the intermediate transfer belt 600, and toner images G1 to G7 to be transferred to the respective sheets P1 to P7 are sequentially formed. The toner images G1 to G7 formed on the intermediate transfer belt 600 are sequentially transferred to sheets P1 to P7 conveyed to a secondary transfer position. The sheet P to which the toner image G has been transferred is conveyed to the fixing device 800 and is heated and pressed, so that the toner image G is fixed on the surface and an image is printed.

  In the state illustrated in FIG. 1, the toner image G1 is fixed on the surface of the sheet P1 that has passed through the fixing device 800, and printing on one surface is completed. The sheet P2 is passing through the fixing device 800, and the toner image G2 is being fixed on the surface. The sheet P3 is in a state where the sheet P3 has passed through the secondary transfer position, the toner image G3 has been transferred to the surface, and is conveyed toward the fixing device 800. The sheets P4 to P7 are conveyed along the conveyance path 210, and toner images G4 to G7 transferred to the sheets P4 to P7 are formed on the intermediate transfer belt 600.

  In the case of single-sided printing, the sheet P having an image formed on one side is discharged from the discharge unit 400 to the outside of the image forming apparatus 100. In the case of double-sided printing, the sheet P having an image formed on one side is transported by being switched back by the reverse transport rollers 303 and 304 and transported along the reverse transport path 211 with the front and back reversed. . After the sheet P has been turned upside down, the toner image is transferred to the other surface again at the secondary transfer position, passes through the fixing device 800, and the image is formed on the other surface. It is discharged out of 100.

  Here, the toner that is not secondarily transferred from the intermediate transfer belt 600 to the sheet P at the secondary transfer position and remains on the intermediate transfer belt 600 is collected by the first cleaning unit 610. The first cleaning unit 610 includes, for example, a cleaning roller that is disposed to face the intermediate transfer belt 600 at a distance, and applies a voltage to the cleaning roller to collect transfer residual toner on the intermediate transfer belt 600.

  The transfer rate of the intermediate transfer belt 600 to the sheet P may be reduced due to abrasion or the like, and the image quality may be reduced. Therefore, it is preferable that the first cleaning unit 610 collects the toner from the intermediate transfer belt 600 in a non-contact manner.

  Further, the secondary transfer roller 601 is provided with a second cleaning unit 611 that collects the toner attached to the surface. The second cleaning unit 611 collects toner adhered to the secondary transfer roller 601 by, for example, bringing a blade, a brush, or the like into contact with the secondary transfer roller 601.

  The first cleaning unit 610 and the second cleaning unit 611 may be of a contact type or a non-contact type as long as the toner can be collected without affecting the image quality. The configurations of the contact system and the non-contact system are not limited to the above-described configurations, respectively, as long as the toner can be collected.

  A plurality of paper sensors 220 are provided in the transport path 210 and the reverse transport path 211 of the paper P. The sheet sensor 220 is, for example, an optical sensor, and detects the sheet P conveyed along the conveyance path 210 or the reverse conveyance path 211. If the paper P is not detected at a predetermined timing by any of the paper sensors 220, it is determined that a transport abnormality (jam) of the paper P has occurred in the transport path 210 or the reverse transport path 211.

  The transport path 210 is provided with a transport belt 301 as an aggregation unit that aggregates the sheets P remaining on the transport path 210 when a jam occurs. The transport belt 301 is provided between the secondary transfer roller 601 and the fixing device 800 on the transport path 210. Further, the image forming apparatus 100 is provided with a paper discharge tray 401 for discharging the paper P remaining on the transport path 210 when a jam occurs.

  In the image forming apparatus 100, when it is determined that a jam has occurred based on the detection result of the paper sensor 220, the paper P remaining in the transport path 210 is collected on, for example, the transport belt 301 or Is discharged.

(Structure and operation of the conveyor belt)
FIG. 2 is a diagram illustrating a schematic configuration of the transport belt 301 in the embodiment. FIG. 3 is a diagram illustrating the operation of the transport belt 301 in the embodiment.

  As shown in FIG. 2, the transport belt 301 includes a driving roller 31, a driven roller 32 as a contact / separation roller, and an endless belt 33.

  The drive roller 31 and the driven roller 32 are provided rotatably, and are provided along the transport path 210. The drive roller 31 is driven to rotate by a drive belt 35 that is rotated by a motor (not shown).

  The endless belt 33 is stretched around the driving roller 31 and the driven roller 32, and rotates following the driving roller 31. When the endless belt 33 rotates, the driven roller 32 rotates following the endless belt 33. When transporting the paper P, the endless belt 33 rotates counterclockwise in FIG. 2 and transports the paper P in the direction of the arrow. Further, as shown in FIG. 3, the endless belt 33 is pressed toward the transport path 210 by a spring 34 as an urging means.

  A cam 38 is provided at one end of the driven roller 32 via a one-way clutch 37. As shown in FIG. 3A, when the endless belt 33 is rotating forward in the direction in which the paper P is conveyed (counterclockwise direction in FIG. 3), the one-way clutch 37 idles and the driven roller 32 The rotational force is not transmitted to the cam 38.

  Further, as shown in FIG. 3B, when the endless belt 33 rotates in the opposite direction (clockwise direction in FIG. 3) to the direction in which the paper P is conveyed, the rotational force of the driven roller 32 is increased by the one-way clutch 37. The power is transmitted to the cam 38, and the cam 38 rotates in the direction of the arrow. When the cam 38 rotates, the cam 38 comes into contact with a fixing member 39 fixedly provided to the image forming apparatus 100, and the driven roller 32 is pushed down so as to be separated from the conveyance path 210.

  In the present embodiment, the cam 38 is provided rotatable by 90 degrees from the state shown in FIG. 3A to the state shown in FIG. By rotating the endless belt 33 so that the cam 38 rotates to a predetermined angle, the separation distance H between the driven roller 32 and the transport path 210 can be adjusted to an arbitrary size. For example, in the state shown in FIG. 3B, the separation distance between the driven roller 32 and the transport path 210 is H1, and in the state shown in FIG. 3C, the distance between the driven roller 32 and the transport path 210 is H1. The separation distance is H2 (> H1).

  For example, by changing the separation distance H between the driven roller 32 and the transport path 210 according to the number of sheets P to be collected on the transport belt 301, the ease of curl of the sheet P, etc. The sheets P can be aggregated so as to overlap in a regular manner. For example, when the number of sheets P to be aggregated is large, or when the sheets P are easily curled, the separation distance H between the driven roller 32 and the transport path 210 is increased. Further, when the number of sheets P to be collected is small, or when the sheets P are of a type that does not easily curl, the separation distance H between the driven roller 32 and the transport path 210 is reduced.

  In this way, by adjusting the position of the driven roller 32 according to the conditions such as the number of sheets P to be collected, the sheets P can be collected so as to be superimposed on the endless belt 33 in an orderly manner. Since the sheets P are collected so as to be orderly stacked on the endless belt 33, the user can easily remove the sheets P collected on the endless belt 33 after the occurrence of the jam.

  When the endless belt 33 is normally rotated in the sheet conveyance direction after the sheet P is removed from the endless belt 33, the cam 38 rotates counterclockwise in FIG. As shown in (A), the driven roller 32 returns to the sheet transport position. When the driven roller 32 approaches the transport path 210 and returns to the paper transport position, the transport belt 301 can transport the paper P again along the transport path 210.

  FIG. 4 is a diagram exemplifying a state where the sheets P are collected on the transport belt 301 in the embodiment. FIG. 4 shows a state in which the paper P2 has jammed in the fixing device 800 from the state shown in FIG. 1 and the paper P3 and the paper P4 are concentrated on the transport belt 301.

  When a jam occurs on the downstream side of the transport belt 301, the paper P remaining on the upstream side of the transport belt 301 is collected on the transport belt 301. First, as shown in FIG. 4A, a sheet P3 onto which the toner image G3 has been transferred at the secondary transfer position between the intermediate transfer belt 600 and the secondary transfer roller 601 is transported to the transport belt 301.

  Next, as shown in FIG. 4B, the cam 38 rotates and the driven roller 32 is pushed down so as to be separated from the conveyance path 210, so that the conveyance belt 301 is inclined. In this state, the sheet P4 passing through the registration roller 302 is conveyed toward the conveyance belt 301 after the toner image G4 is transferred at the secondary transfer position.

  The sheet P4 is transported on the transport belt 301 so as to overlap the sheet P3, as shown in FIG. The sheet P4 is conveyed in a state where the conveyance belt 301 is inclined such that the upstream side is separated from the conveyance path 210, so that the sheet P4 overlaps the sheet P3 without the front end colliding with the rear end of the sheet P3. As described above.

  As described above, since the leading edge of the sheet P4 is collected so as to overlap without colliding with the trailing edge of the sheet P3, contamination inside the apparatus due to scattering of the unfixed toner around is reduced, and the user can easily remove the sheet P. It becomes possible to do.

  The transport belt 301 has the above-described configuration, and when a jam occurs in the image forming apparatus 100, the paper P remaining on the upstream side is collected. Note that the configuration of the transport belt 301 is not limited to the configuration illustrated in the present embodiment.

  For example, the transport belt 301 may be provided so that both the drive roller 31 and the driven roller 32 can be moved toward and away from the transport path 210. In this case, as shown in FIG. 5, when the paper P is collected, both the driving roller 31 and the driven roller 32 are displaced in a direction away from the transport path 210, and the entire transport belt 301 is separated from the transport path 210. Similarly to the above-described embodiment, a plurality of sheets P remaining in the image forming apparatus 100 at the time of occurrence of a jam can be collected so as to be orderly overlapped on the transport belt 301 without causing the succeeding sheet P4 to collide with the preceding sheet P3.

  For example, the transport belt 301 may be configured such that the endless belt 33 is stretched over three or more rollers including one or more contact / separation rollers provided in the transport path 210 so as to be able to contact / separate. The mechanism for moving the contact / separation roller toward and away from the transport path 210 is not limited to the configuration exemplified in the above-described embodiment.

  Note that the image forming apparatus 100 according to the present embodiment is provided with one conveyance belt 301 as a consolidation unit, but a plurality of consolidation units may be provided and may have a configuration different from that of the conveyance belt. . The consolidating unit may be provided on the transport path 210 on the upstream side of the secondary transfer position, or may be provided on the reverse transport path 211.

<Functional Configuration of Image Forming Apparatus>
Next, a functional configuration of the image forming apparatus 100 will be described. FIG. 6 is a block diagram illustrating a functional configuration of the image forming apparatus 100 according to the embodiment.

  As shown in FIG. 6, the image forming apparatus 100 includes a control unit 101, an image forming unit 110, a transport roller 200, a paper sensor 220, an intermediate transfer belt 600, a first cleaning unit 610, a secondary transfer roller 601, and a second transfer unit. It has cleaning means 611.

  The control unit 101 includes an image formation control unit 120, a conveyance control unit 130, a jam detection unit 140 as a jam detection unit, a transfer control unit 150, and a jam processing unit 160 as a jam processing unit. Each function of the control unit 101 is realized, for example, by the CPU reading a program stored in the ROM and executing the program in cooperation with the RAM.

  The image forming control unit 120 controls the image forming unit 110 including the photoconductor 700 and a developing device provided around the photoconductor 700, and forms a toner image on the surface of the photoconductor 700. Further, the image forming control unit 120 transfers the toner image formed on the surface of the photoconductor 700 to the surface of the intermediate transfer belt 600 in a superimposed manner, and forms a full-color toner image on the intermediate transfer belt 600.

  The transport control unit 130 controls the transport roller 200, the transport belt 301, the registration roller 302, and the like, and transports the paper P fed from the paper feed trays 201 and 202 along the transport path 210 or the reverse transport path 211.

  The jam detection unit 140 detects a jam of the sheet P in the transport path 210 and the reverse transport path 211 based on the detection result of the sheet P by the sheet sensor 220 provided in the transport path 210 and the reverse transport path 211. The jam detection unit 140 determines that a jam has occurred, for example, when the paper P is not detected at any of the paper sensors 220 at a predetermined timing.

  The transfer control unit 150 controls the intermediate transfer belt 600 and the secondary transfer roller 601 to secondary transfer the toner image formed on the surface of the intermediate transfer belt 600 to the sheet P conveyed to the secondary transfer position.

  When a jam is detected by the jam detection unit 140, the jam processing unit 160 transmits the conveyance roller 200, the conveyance belt 301, the intermediate transfer belt 600, the secondary transfer roller 601 and the like via the conveyance control unit 130 and the transfer control unit 150. And executes the jam processing.

<Jam processing>
Next, a jam process performed in the image forming apparatus 100 will be described.

(Example 1)
FIG. 7 is a diagram illustrating a flowchart of the jam processing according to the first embodiment.

  When printing is performed in the image forming apparatus 100, the transport control unit 130 transports the paper P fed from the paper feed trays 201 and 202 along the transport path 210 in step S101. On the sheet P, the toner image formed on the intermediate transfer belt 600 at the secondary transfer position is secondarily transferred. The transport control unit 130 further transports the paper P on which the toner image has been transferred and passes it through the fixing device 800, and then discharges the paper P from the discharge unit 400 to the outside of the apparatus. The transport roller 200 and the like are operated so as to transport to the path 211.

  In step S <b> 102, the jam detection unit 140 determines whether or not the paper P conveyed along the conveyance path 210 and the reverse conveyance path 211 is jammed based on the detection result of the paper sensor 220.

  If the passage of the sheet P is detected at a predetermined timing by each of the sheet sensors 220, the jam detecting unit 140 determines that the sheet P is being conveyed normally. If the paper P is being conveyed normally (step S102: NO), the image forming control unit 120 determines in step S103 whether printing is completed. If the printing has not been completed (step S103: NO), the processing after step S101 is executed again. If all the paper P on which the image has been formed on the front surface is discharged from the discharge unit 400 to the outside of the apparatus and the printing is completed (step S103: YES), the processing is terminated.

  If any of the paper sensors 220 does not detect the passage of the paper P at a predetermined timing, the jam detection unit 140 determines that a jam has occurred in the paper P being transported. Further, when the jam detecting unit 140 determines that a jam has occurred, the jam detecting position of the sheet P is grasped based on the detection result of the sheet sensor 220. When a jam is detected by the jam detection unit 140 (step S102: YES), the process proceeds to step S104.

  In step S104, the jam processing unit 160 acquires the transport position of the paper P from the transport control unit 130, and checks whether the paper P exists downstream of the transport belt 301. The downstream side of the transport belt 301 is between the transport belt 301 and the discharge unit 400 in the transport path 210.

  If the sheet P exists downstream of the transport belt 301 (step S104: YES), the jam processing unit 160 executes fixing and discharge of the sheet P downstream of the transport belt 301 in step S105. Before reaching the fixing device 800, the paper P on which the toner image transferred to the surface is not fixed is conveyed to the fixing device 800 and the toner image is fixed. Further, the sheet P having the toner image fixed on the surface after passing through the fixing device 800 is discharged from the discharge unit 400 to the outside of the apparatus as it is, or is transported to the reverse transport path 211.

  In step S <b> 106, the jam processing unit 160 determines whether or not the sheet P exists on the upstream side of the transport belt 301 from the transport position of the sheet P acquired from the transport control unit 130. The upstream side of the transport belt 301 is a portion between the paper feed trays 201 and 202 and the transport belt 301 in the transport path 210 and the reverse transport path 211.

  If the sheet P exists on the upstream side of the transport belt 301 (step S106: YES), in step S107, the jam processing unit 160 checks whether or not the sheet P has passed the registration rollers 302.

  If there is a sheet P that has passed through the registration rollers 302 (step S107: YES), in step S108, the toner image on the intermediate transfer belt 600 is transferred onto the sheet P that has passed through the registration rollers 302, and the toner image is transferred. The transported sheet P is transported to the transport belt 301. If the paper P on which the toner image has been transferred can be transported to the discharge unit 400, the paper P may be discharged from the discharge unit 400 to the outside of the apparatus after passing through the fixing device 800.

  Next, in step S109, the jam processing unit 160 checks the presence or absence of the sheet P before passing through the registration rollers 302 from the transport position of the sheet P acquired from the transport control unit 130.

  If there is a sheet P before passing through the registration rollers 302 (step S109: YES), in step S110, the jam processing unit 160 stops conveyance of the sheet P before passing through the registration rollers 302.

  Next, in step S111, the jam processing unit 160 rotates the cam 38 to displace the driven roller 32, and separates the transport belt 301 from the transport path 210.

  Subsequently, in step S112, the toner image on intermediate transfer belt 600 is transferred to secondary transfer roller 601. In step S113, the second cleaning unit 611 collects the toner transferred to the secondary transfer roller 601.

  After the transfer of the toner image from the intermediate transfer belt 600 to the secondary transfer roller 601 is completed, in step S114, the conveyance of the paper P that has been stopped is restarted, and the paper P before passing through the registration rollers 302 is transferred to the conveyance belt. It is transported to 301.

  In step S115, the jam processing unit 160 displays that a jam has occurred on the display unit of the image forming apparatus 100, for example, and ends the process. Further, the jam processing unit 160 may notify the user's PC or the like that a jam has occurred.

  When the paper jam occurs in the paper P2 in the state illustrated in FIG. 1 by the jam processing in the first embodiment described above, the paper P1 on which the toner image G1 is fixed is discharged from the discharge unit 400 to the outside of the apparatus. When the paper P2 cannot be transported, it stays at the jam occurrence position. When the paper P2 can be transported, the paper P2 passes through the fixing device 800 and the toner image G2 is fixed on the surface, and then discharged from the discharge unit 400 to the outside of the device. You.

  The sheet P3 that has passed through the registration roller 302 is conveyed to the conveyance belt 301 with the toner image G3 transferred to one surface, or when the sheet P2 is discharged out of the apparatus, the fixing device is used. The sheet is discharged from the discharge unit 400 to the outside of the apparatus through the line 800.

  Conveyance of the sheets P4 to P7 upstream of the registration rollers 302 is temporarily stopped when a jam is detected. While the conveyance of the sheets P4 to P7 is stopped, the toner images G4 to G7 formed on the intermediate transfer belt 600 are transferred to the secondary transfer roller 601 and collected by the second cleaning unit 611.

  After the toner images G4 to G7 on the intermediate transfer belt 600 are transferred to the secondary transfer roller 601 and collected by the second cleaning unit 611, the conveyance of the sheets P4 to P7 is resumed, and the sheets P4 to P7 are stacked on the conveyance belt 301. Aggregated.

  FIG. 8 is a diagram illustrating a case where a paper jam has occurred on the sheet P2 from the state illustrated in FIG. 1 and illustrating a state of the image forming apparatus 100 after the jam processing.

  As shown in FIG. 8, the sheet P2 stays at the jam occurrence position, and the sheets P3 to P7 are conveyed by the conveying belt 301 and are gathered so as to overlap. The toner images G4 to G7 formed on the intermediate transfer belt 600 are transferred to the secondary transfer roller 601 and collected by the second cleaning unit 611.

  As described above, the toner image formed on the intermediate transfer belt 600 at the time of the occurrence of the jam is transferred to the secondary transfer roller 601 and collected by the second cleaning unit 611. Therefore, the first cleaning unit 610 that collects the transfer residual toner on the surface of the intermediate transfer belt 600 only needs to collect the transfer residual toner on the intermediate transfer belt 600, and the processing load is reduced.

  Therefore, the occurrence of problems such as toner overflow, contamination in the apparatus, and printing failure due to contamination of the recording medium caused by the first cleaning unit 610 collecting untransferred toner exceeding the collection capacity during jam processing is suppressed.

  Further, the paper P that has been transported on the upstream side of the registration roller 302 at the time of the occurrence of the jam is collected on the transport belt 301 in a state of a blank sheet without transferring the toner image. For this reason, the user can take out the sheets P collected on the transport belt 301 without soiling the hands with the unfixed toner before passing through the fixing device 800.

  Further, when the paper P is gathered, the transport belt 301 is separated from the transport path 210, so that the paper P is orderly overlapped and aggregated on the transport belt 301 without being scattered. Therefore, the user can easily take out the aggregated paper P.

(Example 2)
FIG. 9 is a diagram illustrating a flowchart of the jam processing according to the second embodiment.

  The processing contents of steps S201 to S209 in the jam processing of the second embodiment illustrated in FIG. 9 are the same as the processing contents of steps S101 to S109 in the jam processing of the first embodiment, and a description thereof will be omitted.

  In step S210, the jam processing unit 160 acquires the image area ratio of the toner image formed on the intermediate transfer belt 600 from the image formation control unit 120.

  The image area ratio is obtained based on, for example, the following equation.

Image area ratio [%] = (area of toner image / area of image forming area) × 100
Further, when a plurality of toner images to be respectively transferred to different papers P are formed on the intermediate transfer belt 600, the jam processing unit 160 determines the average value, the maximum value, or the minimum value of the image area ratio of each toner image. The value may be obtained as the image area ratio.

  If the image area ratio of the toner image is equal to or more than N% (step S210: YES), the jam processing unit 160 stops the conveyance of the sheet P before passing through the registration rollers 302 in step S211. Next, in step S212, the jam processing unit 160 rotates the cam 38 to displace the driven roller 32, and separates the transport belt 301 from the transport path 210.

  Subsequently, in step S213, the toner image on the intermediate transfer belt 600 is transferred to the secondary transfer roller 601. In step S214, the second cleaning unit 611 collects the toner transferred to the secondary transfer roller 601.

  Subsequently, in step S217, the sheet P before passing through the registration rollers 302 is conveyed to the conveying belt 301 in a state of a blank sheet and collected.

  If the image area ratio of the toner image is less than N% (step S211: NO), the jam processing unit 160 transfers the toner image formed on the intermediate transfer belt 600 to the sheet P in step S215. . Next, in step S216, the first cleaning unit 610 collects the untransferred toner on the intermediate transfer belt 600.

  Subsequently, in step S217, the paper P being transported upstream of the registration rollers 302 at the time of the occurrence of the jam is transported to the transport belt 301 in a state where the toner image has been transferred, and collected.

  The threshold value N [%] with which the jam processing unit 160 compares the image area ratios is appropriately set based on, for example, the toner collecting ability of the first cleaning unit 610 and the second cleaning unit 611.

  In step S218, the jam processing unit 160 displays that a jam has occurred on the display unit of the image forming apparatus 100, for example, and ends the processing.

  When the image area ratio of the toner image on the intermediate transfer belt 600 is high due to the jam processing in the second embodiment described above, the toner image on the intermediate transfer belt 600 is transferred to the secondary transfer roller 601 and The cleaning unit 611 collects the untransferred toner. When the image area ratio of the toner image on the intermediate transfer belt 600 is low, the first cleaning unit 610 collects the untransferred toner.

  Thus, the untransferred toner formed on the intermediate transfer belt 600 at the time of the occurrence of the jam is collected by the second cleaning unit 611 when the image area ratio is high. Therefore, the amount of toner collected by the first cleaning unit 610 when a jam occurs is reduced, and the processing load on the first cleaning unit 610 is reduced.

  Therefore, the occurrence of problems such as toner overflow, contamination in the apparatus, and printing failure due to contamination of the recording medium, etc., caused by the first cleaning unit 610 collecting the transfer residual toner exceeding the collecting ability at the time of the jam processing is suppressed.

(Example 3)
FIG. 10 is a diagram illustrating a flowchart of the jam processing according to the third embodiment.

  The processing contents of steps S301 to S309 in the jam processing of the third embodiment illustrated in FIG. 10 are the same as the processing contents of steps S101 to S109 in the jam processing of the first embodiment, and a description thereof will be omitted.

  If the paper P before passing through the registration rollers 302 remains in the conveyance path 210 at the time of the occurrence of the jam, in step S310, the jam processing unit 160 rotates the cam 38 to displace the driven roller 32, and the conveyance belt 301 Is separated from the transport path 210. Next, in step S311, the jam processing unit 160 acquires the image area ratio of the toner image formed on the intermediate transfer belt 600 from the image formation control unit 120.

  If the image area ratio of the toner image is equal to or greater than N% (step S311: YES), in step S312, the jam processing unit 160 determines that the transfer rate from the intermediate transfer belt 600 to the sheet P is lower than that during normal printing. Change the transfer conditions so that The jam processing unit 160 reduces the transfer rate T from the intermediate transfer belt 600 to the sheet P by, for example, making the transfer current lower than that during normal printing, so that the transfer rate T from the normal first transfer rate T1 [%] to the second transfer rate It is reduced to T2 (<T1).

  Next, in step S313, the toner image on the intermediate transfer belt 600 is transferred onto the sheet P under the set transfer conditions. Further, in step S314, the sheet P on the upstream side of the registration roller 302 at the time of the occurrence of the jam, on which the toner image has been transferred, is conveyed to the conveyance belt 301 and collected.

  In step S315, the jam processing unit 160 displays that a jam has occurred on the display unit of the image forming apparatus 100, for example, and ends the processing.

  When the image area ratio of the toner image on the intermediate transfer belt 600 is high, at least a part of the toner on the intermediate transfer belt 600 is transferred to the sheet P by the jam processing in the third embodiment described above. For this reason, when a jam occurs, the amount of toner collected by the first cleaning unit 610 is reduced, and the processing load on the first cleaning unit 610 is reduced.

  Therefore, the occurrence of problems such as toner overflow, contamination in the apparatus, and printing failure due to contamination of the recording medium, etc., caused by the first cleaning unit 610 collecting the transfer residual toner exceeding the collecting ability at the time of the jam processing is suppressed.

  As described above, according to the image forming apparatus 100 of the present embodiment, the load of the untransferred toner processing of the first cleaning unit 610 provided on the intermediate transfer belt 600 is reduced when a jam occurs. Therefore, the occurrence of various problems caused by the first cleaning unit 610 collecting the toner exceeding the collecting ability at the time of the occurrence of a jam is reduced.

  As described above, the image forming apparatus and the image forming method according to the embodiment have been described, but the present invention is not limited to the above embodiment, and various modifications and improvements can be made within the scope of the present invention.

100 image forming apparatus 110 image forming means 140 jam detecting section (jam detecting means)
160 Jam processing unit (jam processing means)
301 Conveyor belt (collecting means)
600 Intermediate transfer belt (intermediate transfer body)
601 Secondary transfer roller (transfer means)
610 First cleaning means 611 Second cleaning means P Paper (recording medium)

Japanese Patent No. 4909206

Claims (9)

Image forming means for forming a toner image on the intermediate transfer member,
A transfer unit that is disposed to face the intermediate transfer body, and that secondarily transfers the toner image to a recording medium at a secondary transfer position between the intermediate transfer body and
First cleaning means for collecting toner remaining on the intermediate transfer member;
A second cleaning unit that collects toner attached to the transfer unit;
Conveying means for conveying the recording medium along a conveying path,
An aggregation unit provided on the downstream side of the secondary transfer position in the transport path and configured to aggregate a plurality of recording media;
Jam detection means for detecting a jam of a recording medium conveyed along the conveyance path,
And a jam processing unit that controls the transfer unit and the transport unit to execute a jam process when a jam is detected by the jam detection unit,
When the jam is detected and untransferred toner is present in the intermediate transfer body, the jam processing unit transfers the untransferred toner from the intermediate transfer body to the transfer unit and collects the untransferred toner in the second cleaning unit. The image forming apparatus according to claim 1, wherein the recording medium existing on the upstream side of the secondary transfer position is conveyed to the consolidating unit . Image forming means for forming a toner image on the intermediate transfer member,
A transfer unit that is disposed to face the intermediate transfer body, and that secondarily transfers the toner image to a recording medium at a secondary transfer position between the intermediate transfer body and
First cleaning means for collecting toner remaining on the intermediate transfer member;
A second cleaning unit that collects toner attached to the transfer unit;
Conveying means for conveying the recording medium along a conveying path,
Jam detection means for detecting a jam of a recording medium conveyed along the conveyance path,
And a jam processing unit that controls the transfer unit and the transport unit to execute a jam process when a jam is detected by the jam detection unit,
The jam processing unit is configured to remove the untransferred toner when the jam is detected and untransferred toner is present in the intermediate transfer body, and when the image area ratio of the untransferred toner is equal to or greater than a predetermined value. The image is transferred from the intermediate transfer body to the transfer unit and collected by the second cleaning unit. When the image area ratio of the untransferred toner is less than the predetermined value, the untransferred toner is transferred to the first cleaning unit. An image forming apparatus characterized by being collected. Image forming means for forming a toner image on the intermediate transfer member,
A transfer unit that is disposed to face the intermediate transfer body, and that secondarily transfers the toner image to a recording medium at a secondary transfer position between the intermediate transfer body and
Cleaning means for collecting toner remaining on the intermediate transfer member;
Conveying means for conveying the recording medium along a conveying path,
Jam detection means for detecting a jam of a recording medium conveyed along the conveyance path,
And a jam processing unit that controls the transfer unit and the transport unit to execute a jam process when a jam is detected by the jam detection unit,
The jam processing unit is configured to determine whether the untransferred toner is present on the intermediate transfer member when the jam is detected and the image area ratio of the untransferred toner is less than a predetermined value. wherein by transferring the untransferred toner on the recording medium, wherein when the image area ratio of the non-transferred toner is the predetermined value or more, said recording medium the toner not transferred by the second transfer rate lower than the first transfer rate An image forming apparatus characterized in that the image is transferred to an image forming apparatus.   Equipped with a display unit,
  The jam processing unit includes, when the jam is detected and the untransferred toner is present in the intermediate transfer body, a process of discharging a recording medium existing downstream of the collecting unit to the outside of the apparatus; and Transfer from the intermediate transfer member to the transfer unit and collection by the second cleaning unit, and then transport the recording medium existing upstream of the secondary transfer position to the collecting unit. After that, displaying that a jam has occurred on the display unit,
The image forming apparatus according to claim 1, wherein: The consolidating means conveys a recording medium along the transport path by rotating a plurality of rollers including a plurality of rollers including a contact / separation roller provided so as to be capable of coming and going on the transport path and rotating the plurality of rollers. And a transport belt,
The image forming apparatus according to claim 1 , wherein the jam processing unit separates the contact / separation roller from the conveyance path when collecting the recording media. The image forming apparatus according to claim 5, wherein a distance between the contact roller and the conveyance path is variably provided. The consolidating means is connected via a one-way clutch to the contact / separation roller which rotates following the conveyance belt, and the contact / separation roller is rotated when the conveyance belt rotates in a direction opposite to a recording medium conveyance direction. Having a cam that rotates together with the fixed member,
The apparatus according to claim 1, wherein the jam processing unit rotates the transport belt in a reverse direction when the recording media are aggregated, causes the cam to contact the fixed member, and separates the contact / separation roller from the transport path. 7. The image forming apparatus according to 5 or 6. 8. The apparatus according to claim 1, wherein when the jam is detected, the jam processing unit discharges a recording medium existing downstream of the secondary transfer position in the transport path to the outside of the apparatus. 9. The image forming apparatus according to claim 1. Image forming means for forming a toner image on the intermediate transfer member,
A transfer unit that is disposed to face the intermediate transfer body, and that secondarily transfers the toner image to a recording medium at a secondary transfer position between the intermediate transfer body and
Cleaning means for collecting toner adhered to the transfer means,
Conveying means for conveying the recording medium along a conveying path,
An aggregation unit that is provided on the downstream side of the secondary transfer position in the transport path and that aggregates a plurality of recording media;
An image forming method in an image forming apparatus having
A jam detection step of detecting a jam of the recording medium conveyed along the conveyance path,
A transfer step of transferring the untransferred toner from the intermediate transfer body to the transfer unit when the jam is detected and untransferred toner is present on the intermediate transfer body;
A collection step in which the cleaning unit collects the untransferred toner transferred to the transfer unit;
Transporting a recording medium present upstream of the secondary transfer position to the collecting means after the collecting step;
An image forming method comprising:

Images