JP6335662B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus that forms an image on a sheet, and more particularly to jam processing when a sheet jam (hereinafter referred to as jam) occurs.

  2. Description of the Related Art Conventionally, image forming apparatuses such as copying machines and printers have been designed on the assumption that jamming will occur because it is difficult to eliminate sheet jamming. For example, there is an image forming apparatus that is provided with a plurality of doors that are opened and closed for jamming processing and that can remove a jammed sheet by releasing any of the doors.

  When a jam occurs, normally all the sheets being conveyed are stopped, so that not only the jammed sheet but also a sheet that is normally conveyed remains in the image forming apparatus. Therefore, when a jam occurs, the user must remove not only the jammed sheet but also other sheets remaining in the apparatus.

  In order to reduce the user's trouble, the image forming unit reverses the front and back of the sheet on which the image is formed on the first surface of the sheet, and the reversing feeding unit that conveys the sheet to the image forming unit again There has been proposed an image forming apparatus configured to be able to be pulled out from a camera (see Patent Document 1). The image forming apparatus includes a residual paper storage unit below the reverse feeding unit, and conveys and stores the sheet remaining in the reverse feeding unit to the residual paper storage unit when a jam occurs. The remaining sheet is configured not to be in the way of pulling out the reverse feeding unit from the apparatus main body.

  Further, the position of the sheet remaining in the apparatus when the jam occurs is detected, and the sheet is straddled between the apparatus main body and a fixing conveyance unit provided so as to be able to be pulled out with respect to the apparatus main body. There has been proposed an image forming apparatus that transports to a position where it stops and stops (see Patent Document 2).

JP 2003-12214 A JP 09-048539 A

  By the way, the occurrence of a jam often occurs in the vicinity of a transfer unit that transfers an image to a sheet or a fixing unit that fixes the image to a sheet. For example, when a jam occurs in a fixing unit, Usually, it is in the vicinity of the registration roller for correcting the skew of the sheet. For this reason, there have been many requests for an image forming apparatus capable of easily removing a sheet remaining in the vicinity of a registration roller when a jam occurs.

  However, the image forming apparatus described in Patent Document 1 can convey only the sheet remaining in the reversal feeding unit to the remaining paper storage unit, and can easily remove the sheet remaining in the vicinity of the registration roller. could not. Further, in the image forming apparatus described in Patent Document 2, when a jam occurs in the vicinity of the transfer unit or the fixing unit, a sheet subsequent to the jammed sheet does not straddle between the apparatus main body and the fixing conveyance unit. Try to force transport. Then, the jammed sheet and the forcibly conveyed subsequent sheet collide, and the subsequent sheet stops at a position straddling the apparatus main body and the fixing conveyance unit. If the fixing conveyance unit is pulled out in this state, the sheet may be damaged and a piece of paper may remain in the apparatus. Even if the succeeding sheet does not collide with the jammed sheet, if the succeeding sheet is transported from the vicinity of the registration roller to the image forming section where the image is prepared, unfixed toner on the image forming section is removed from the apparatus. There is a risk of splashing inside.

  Therefore, the present invention is configured so that the remaining sheet remaining in the apparatus when a jam occurs is conveyed to the storage means without being conveyed to the image forming means, thereby solving the above-described problems. The purpose is to provide.

  In the image forming apparatus, the image forming apparatus includes a skew correction unit that corrects the skew of the sheet, and includes a conveyance unit that conveys the sheet, and an image formation unit that forms an image on the sheet conveyed by the conveyance unit; In order to remove the sheet in the apparatus, the drawing means that can be pulled out in the drawing direction orthogonal to the sheet conveyance direction, and when the sheet jam occurs, on the upstream side of the skew feeding correction means in the conveyance direction, A residual sheet detecting means for detecting a residual sheet remaining across the boundary between the drawing means and the apparatus main body, a storage means for storing the residual sheet, the residual sheet, the image forming means, and the storage; A guide means for selectively guiding, a leading edge detection means for detecting a position of a leading edge of the residual sheet in the transport direction, and the residual sheet detection means And when it is determined that the leading edge of the remaining sheet in the conveying direction is upstream of the guiding means in the conveying direction based on the detection result of the leading edge detecting means. Control means for controlling the guide means so that the remaining sheet is guided, and control means for controlling the transport means so that the residual sheet is transported to the storage means.

  According to the present invention, when a jam occurs, a residual sheet remaining across the boundary between the drawing unit and the apparatus main body on the upstream side in the conveyance direction of the skew feeding correction unit is detected. When it is determined that it is located upstream, it is transported to the storage means. As a result, the remaining sheet is transported to a position where it does not straddle the boundary without colliding with the jammed sheet, so that when the drawing means is pulled out, the remaining sheet is broken and a piece of paper remains in the apparatus. Can be prevented. Further, since the residual sheet is conveyed to the storage unit, the residual sheet is not conveyed to the image forming unit, and the toner on the image forming unit is scattered in the apparatus and the residual sheet is contaminated. Can be prevented.

1 is an overall cross-sectional view showing a printer according to a first embodiment of the present invention. The control block diagram which concerns on the 1st Embodiment of this invention. It is sectional drawing which shows the drawer unit and residual sheet which concern on the 1st Embodiment of this invention, (a) is the state where four residual sheets straddled the drawer unit, (b) remains in the residual sheet storage part. The seat is being guided. (C) is a state in which residual sheets are stored in the residual sheet storage unit, and (d) is a state in which all four residual sheets are not straddled on the drawer unit. 3 is a flowchart showing jam processing control according to the first embodiment of the present invention. 10 is another flowchart showing jam processing control according to the first embodiment of the present invention. Sectional drawing which shows the modification concerning the 1st Embodiment of this invention. Sectional drawing which shows the drawer unit and residual sheet which concern on the 2nd Embodiment of this invention.

(First embodiment)
First, a first embodiment of the present invention will be described. The image forming apparatus according to the embodiment of the present invention may be any apparatus including an image forming unit that forms an image on a sheet, such as a copying machine, a printer, a facsimile machine, and a multifunction machine of these. The following embodiments will be described using an electrophotographic laser beam printer (hereinafter referred to as a printer) 1 that forms four color toner images.

  As shown in FIG. 1, the printer 1 includes a feeding unit 10 that feeds stacked sheets, an image forming unit 30 that forms an image on a sheet, a discharge unit 50 that discharges sheets to the outside, and a printer 1. And a control unit 70 (control means) for controlling operations necessary for image formation. The feeding unit 10 feeds a plurality of sheet stacking units 11A, 11B, 11C, and 11D (sheet stacking unit) on which the sheets S are stacked and the sheets S stacked on the sheet stacking unit while separating them one by one. And feeding rollers 12A, 12B, 12C, and 12D (feeding means). In this embodiment, the sheet stacking unit is provided in four stages, but may be provided in one to three stages or five or more stages.

  The sheet S fed by the feeding rollers 12A, 12B, and 12C is conveyed to the registration roller 19 (skew correction unit) by the conveying rollers 14, 15, 16, and 17 and the pre-registration roller 18 on the conveying path 13. Is done. The sheet S fed to the double-sided conveyance path 20 described later by the feeding roller 12D is conveyed to the registration roller 19 by the conveyance rollers 21, 22, 23 and the pre-registration roller 18. The registration roller 19 abuts the conveyed sheet S and forms a loop on the sheet S, thereby correcting the skew by following the leading edge of the sheet S. Further, the registration roller 19 adjusts the timing of image formation on the sheet S by conveying the sheet S at a predetermined timing in accordance with a toner image carried on an intermediate belt, which will be described later.

  The image forming unit 30 includes four process cartridges 31Y, 31M, 31C, and 31K that form images of four colors of yellow (Y), magenta (M), cyan (C), and black (K). Since the four process cartridges 31Y, 31M, 31C, and 31K have the same configuration except that the colors of the images to be formed are different, the configuration of the process cartridge 31Y will be described, and the process cartridges 31M, 31C, and 31K will be described. Omitted. The process cartridge 31Y includes a photosensitive drum 32Y that is rotationally driven by a stepping motor, a charging roller 33Y that charges the photosensitive drum 32Y, and a developing device 34Y that develops the electrostatic latent image formed on the photosensitive drum 32Y. Yes. The image forming unit 30 irradiates the photosensitive drums 32Y, 32M, 32C, and 32K of each process cartridge with a laser beam based on the image information, and forms an electrostatic latent image on the photosensitive drums 35Y, 35M, and 35C. , 35K.

  The image forming unit 30 also includes an intermediate transfer belt 36 on which a toner image on a photosensitive drum (for example, 32Y) of each process cartridge is primarily transferred, and primary transfer rollers 37Y and 37M that primarily transfer the toner image to the intermediate transfer belt 36. , 37C, 37K. The intermediate transfer belt 36 is rotated by a driving roller 44 in synchronization with the outer peripheral speed of the photosensitive drums 32Y, 32M, 32C, and 32K, and is stretched around a tension roller 39 that applies appropriate tension to the driven roller 38 and the intermediate transfer belt 36. Has been. Further, the image forming unit 30 includes a secondary transfer roller 40 that secondary-transfers the primary-transferred toner image onto the sheet S, a pre-fixing conveying device 41, and a fixing unit 42 that heat-fixes the secondary-transferred toner image. And. The sheet S that has passed through the fixing unit 42 is conveyed to the discharge unit 50 by the conveyance roller 46. Note that after the toner images on the photosensitive drums 32Y, 32M, 32C, and 32K are transferred to the intermediate transfer belt 36, the toner remaining on the photosensitive drums is collected by the photoreceptor cleaners 43Y, 43M, 43C, and 43K.

  The discharge unit 50 includes a discharge conveyance path 51, a discharge roller 53 that discharges the sheet S to the discharge tray 52, a reverse conveyance path 54, and the sheet S conveyed to the discharge conveyance path 51. 54, and a guide member 55 that guides alternatively. The guide member 55 is configured to be rotatable by a solenoid (not shown). In the reverse conveyance path 54, a reverse roller 56 whose rotation direction can be rotated forward and backward, and a plurality of conveyance rollers 57, 58, and 59 for conveying the sheet S on the reverse conveyance path 54 are arranged. The sheet conveyed with its leading edge and trailing edge reversed by the reversing roller 56 is guided to the duplex conveying path 20 and conveyed to the registration roller 19 by the conveying rollers 60, 61, 22, 23 and the pre-registration roller 18. The The conveyance rollers 60, 61, 22, and 23 constitute double-sided conveyance means.

  When an image formation command is output to the printer 1, based on the input image information, the scanners 35Y, 35M, 35C, and 35K perform lasers toward the photosensitive drums (for example, 31Y) of the process cartridges 31Y, 31M, 31C, and 31K. Irradiate light. At this time, the photosensitive drum is charged in advance by a charging roller (for example, 33Y), and an electrostatic latent image is formed on the photosensitive drum by irradiation with laser light. Thereafter, the electrostatic latent image is developed by a developing device (for example, 34Y), and toner images of yellow (Y), magenta (M), cyan (C), and black (K) are formed on each photosensitive drum. Each color toner image formed on each photosensitive drum is transferred onto the intermediate transfer belt 36 in a superimposed manner by applying a transfer bias to the intermediate transfer belt 36 by the primary transfer rollers 37Y, 37M, 37C, and 37K. The The toner image transferred to the intermediate transfer belt 36 is conveyed to the secondary transfer roller 40 by driving of the driving roller 44.

  In parallel with the image forming operation described above, the sheets S stacked on the feeding unit 10 are fed one by one toward the registration roller 19. The skew is corrected by the registration roller 19, and the sheet S conveyed at a predetermined conveyance timing is sandwiched between the intermediate transfer belt 36 and the secondary transfer roller 40 and conveyed to the pre-fixing conveyance device 41. . When the sheet S passes through the nip portion 45 (image forming means) between the intermediate transfer belt 36 and the secondary transfer roller 40, the toner on the intermediate transfer belt 36 is transferred by the transfer bias applied by the secondary transfer roller 40. The image is transferred. The sheet S to which the toner image has been transferred is conveyed to the fixing unit 42 by the pre-fixing conveying device 41, and is pressed and heated by the fixing unit 42, whereby the toner image is fixed. Then, the sheet S that has passed through the fixing unit 42 is discharged onto the discharge tray 52 by the discharge roller 53.

  When images are formed on both surfaces of the sheet S, the sheet on which the image is formed on the first surface by the secondary transfer roller 40 is guided toward the reverse conveyance path 54 by the guide member 55. Then, the sheet S is guided to the double-sided conveyance path 20 after the leading edge and the trailing edge of the sheet are reversed by the reversing roller 56. Then, the sheet S is conveyed again to the registration roller 19, an image is formed on the second surface by the secondary transfer roller 40, and is discharged onto the discharge tray 52.

  In the printer 1 of the present embodiment, as shown in FIG. 1, the registration roller 19, the nip portion 45, the pre-fixing conveyance device 41, the fixing portion 42, and the double-side conveyance path 20 are connected to one drawer unit 80 (drawing unit). It is configured as a part. The pull-out unit 80 can be pulled out in a pull-out direction perpendicular to the sheet transport direction (hereinafter simply referred to as the transport direction). The pull-out direction is a pull-out direction toward the front side operated by the user, and a portion excluding the pull-out unit 80 from the printer 1 is defined as a printer main body 1A (apparatus main body). The drawer unit 80 is configured so that the transport rollers 22, 23, 46, 60, 61 and the pre-registration roller 18 can also be pulled out from the printer 1. By configuring the drawer unit 80 in this way, when a jam occurs, the user can pull out the drawer unit 80 from the printer 1 and easily perform the jam processing. Also, maintenance can be easily performed.

  Here, a case where a jam occurs upstream in the conveyance direction of the fixing unit 42 will be described. The sheet causing the jam is referred to as a jam sheet SJ. As shown in FIG. 1, when the jam sheet SJ is jammed between the nip portion 45 and the fixing portion 42, there are a maximum of four remaining sheets S1, S2, S3, and S4 stopped in the printer 1. . The residual sheet S1 straddles the boundary B1 between the drawer unit 80 and the printer main body 1A on the upstream side of the registration roller 19 in the transport direction. The residual sheet S2 (fixed residual sheet) straddles the boundary portion B2 (fixing boundary portion) between the drawer unit 80 and the printer main body 1A on the downstream side of the fixing portion 42 in the transport direction. The residual sheet S3 (double-sided residual sheet) is a boundary part B3 (double-sided boundary part) between the drawer unit 80 and the printer main body 1A on the upstream side of the conveyance rollers 60, 61, 22, and 23 as double-sided conveyance means in the conveyance direction. ). The residual sheet S4 (feed residual sheet) straddles the boundary B4 (feed boundary) between the drawer unit 80 and the printer main body 1A on the downstream side of the feed roller 12D in the transport direction.

  Therefore, when these residual sheets S1, S2, S3, and S4 are in the positions shown in FIG. 1 or FIG. 3A, they are broken when trying to pull out the drawer unit 80 from the printer 1. Alternatively, when the drawer unit 80 is to be pulled out from the printer main body 1A, the remaining sheets S1, S2, S3, and S4 cannot be pulled out due to resistance, and the jammed sheet SJ may not be removed.

  In the boundary portions B1, B2, B3, and B4, there are residual sheet detection units SN1, SN2, SN3, and SN4 that detect the residual sheets S1, S2, S3, and S4 straddling between the drawer unit 80 and the printer main body 1A, respectively. Has been placed. A residual sheet detection unit SN5 (front end detection unit) that detects the position of the front end (downstream end in the transport direction) of the residual sheet S1 is disposed upstream of the registration roller 19 in the transport direction. Below the registration roller 19, a residual sheet storage portion 81 that stores the residual sheet S1 is disposed. Further, on the downstream side of the registration roller 19 in the conveying direction, a guide member 82 (guide) that selectively guides the residual sheet S1 that has passed through the registration roller 19 to the nip portion 45 and the residual sheet storage portion 81. Means) are arranged.

  FIG. 2 shows a control block diagram in the present embodiment, and the control unit 70 has a CPU, a ROM, a RAM, and the like (not shown). Residual sheet detectors SN1, SN2, SN3, SN4, and SN5, a stack detector 83, a sheet size detector 84, and a discharge detector 85 are connected to the input side of the controller 70. The stack detection unit 83 detects the residual sheet S1 stacked in the residual sheet storage unit 81. The sheet size detection unit 84 detects the size of the sheets stacked on the sheet stacking units 11A, 11B, 11C, and 11D. The discharge detection unit 85 detects the remaining sheet S <b> 2 at the discharge roller 53.

  A pre-registration motor 86, a registration motor 87, a transport motor 88, a switching solenoid 89, and an operation display panel 90 are connected to the output side of the control unit 70. The pre-registration motor 86 drives the pre-registration roller 18, and the registration motor 87 drives the registration roller 19. The conveyance motor 88 drives the conveyance rollers 14, 15, 16, 17, 21, 22, 23, 46, 57, 58, 59, 60, and 61, but not by a single motor but by a plurality of motors. You may comprise as follows. These pre-registration roller 18, registration roller 19, reversing roller 56 and conveying rollers 14, 15, 16, 17, 21, 22, 23, 46, 57, 58, 59, 60, 61 are conveying means for conveying the sheet. Configure. The switching solenoid 89 drives the guide member 82 to switch the direction in which the remaining sheet S1 is guided. In this embodiment, the guide member 82 is driven by a solenoid, but another actuator may be used instead of the solenoid. The operation display panel 90 can perform various settings by a touch operation. When a jam occurs, the occurrence of the jam is notified.

  Next, jam processing control for forcibly conveying the remaining sheets S1, S2, S3, and S4 when the printer 1 has jammed will be described with reference to FIGS. When a jam occurs in the printer 1, the sheet conveyed in the printer 1 stops. In the present embodiment, as shown in FIG. 3A, the jammed sheet SJ is jammed between the fixing unit 42 and the nip 45, and the remaining sheets S1, S2, S3, and S4 remain in the printer 1. doing. The printer 1 starts jam processing control when a jam occurs.

  When the jam processing control is started, the control unit 70 determines whether the sheet is fed only from the sheet stacking unit 11D (step S11). If it is determined in step S11 that the sheet is fed only from the sheet stacking unit 11D, the sheet does not straddle the boundary B1, and the process proceeds to step S13. If it is determined in step S11 that a sheet is being fed from other than the sheet stacking unit 11D, that is, from the sheet stacking units 11A, 11B, and 11C, the control unit 70 determines that the sheet at the head of the job is sent to the sheet detection unit SN1. It is determined whether or not it has been reached (step S12). If the sheet at the head of the job has not reached the remaining sheet detection unit SN1, the control unit 70 stops the operation of the printer 1, and the jammed sheet and the remaining sheet in the feeding unit 10 are detected. It is displayed on the operation display panel 90 (step S25). Thereby, it is possible to prompt the user to perform jam processing on the sheet.

  If it is determined in step S12 that the sheet at the head of the job has reached the remaining sheet detection unit SN1, the control unit 70 assumes that the remaining sheet S1 straddles the boundary B1. Then, the control unit 70 determines whether or not the residual sheet S1 has reached the registration roller 19 based on the detection result of the residual sheet detection unit SN5 (step S13). If it is determined in step S13 that the leading edge of the residual sheet S1 is upstream of the registration roller 19 in the transport direction, the control unit 70 guides the residual sheet S1 to the residual sheet storage unit 81. 82 is driven (step S14). Then, as shown in FIGS. 3B and 3C, the control unit 70 drives the registration roller 19 and the pre-registration roller 18, for example, to convey the residual sheet S1 to the residual sheet storage unit 81 (step). S15), the process proceeds to step S18.

  When it is determined in step S13 that the residual sheet S1 has reached the registration roller 19, the control unit 70 determines that the trailing edge of the residual sheet S1 is in the conveyance direction of the boundary portion B1 based on the detection result of the residual sheet detection unit SN1. It is determined whether or not it is upstream (step S16). If it is determined in step S16 that the trailing edge of the residual sheet S1 is upstream in the conveying direction of the boundary B1, for example, the pre-registration roller 18 and the conveying roller 17 are driven, and the trailing edge of the residual sheet S1 is pulled out. 80 (step S17), and proceeds to step S18. At this time, the rear end of the residual sheet S1 is conveyed while the registration roller 19 to which the residual sheet S1 has reached and the roller downstream of the registration roller 19 in the conveyance direction are stopped. As a result, the leading edge in the conveyance direction of the residual sheet S1 is not conveyed to the nip portion 45 by the registration roller 19 or the like, and unfixed toner on the nip portion 45 is scattered in the apparatus or the residual sheet S1. Can be prevented from being contaminated. If it is determined in step S16 that the trailing edge of the residual sheet S1 is not upstream in the conveyance direction of the boundary portion B1, it is determined that the residual sheet S1 does not straddle the boundary portion B1, and the process proceeds to step S18. Thus, first, the conveyance control of the remaining sheet S1 is completed.

  Next, the control unit 70 determines whether or not the residual sheet S4 extends over the boundary portion B4 based on the detection result of the residual sheet detection unit SN4 (feeding residual sheet detection unit) (step S18). If it is determined in step S18 that the residual sheet S4 is straddling the boundary portion B4, the control unit 70 drives, for example, the transport rollers 21 and 22 so that the rear end of the residual sheet S4 is brought into the drawing unit 80. (Step S19). Here, at least the rear end of the residual sheet S4 may be conveyed into the drawing unit 80, but it is preferable to convey not only the rear end of the residual sheet S4 but also the entire residual sheet S4. However, considering the position and size of the sheet preceding the remaining sheet S4, when the remaining sheet S4 collides with the preceding sheet, only the rear end of the remaining sheet S4 is conveyed.

  Next, the control unit 70 determines whether or not the residual sheet S3 straddles the boundary portion B3 based on the detection result of the residual sheet detection unit SN3 (double-sided residual sheet detection unit) (step S20). If it is determined in step S20 that the remaining sheet S3 is straddling the boundary portion B3, the control unit 70 drives the reverse roller 56, for example, and conveys the rear end of the remaining sheet S3 into the drawing unit 80. (Step S19).

  Next, the control unit 70 determines whether or not the residual sheet S2 straddles the boundary portion B2 based on the detection result of the residual sheet detection unit SN2 (fixed residual sheet detection unit) (step S21). If it is determined in step S21 that the residual sheet S2 is straddling the boundary portion B2, the control unit 70 determines whether the discharge roller 53 holds the residual sheet S2 based on the detection result of the discharge detection unit 85. It is determined whether or not (step S22). If it is determined in step S22 that the discharge roller 53 holds the residual sheet S2, the control unit 70 drives the discharge roller 53 to discharge the residual sheet S2 to the discharge tray 52 (step S23). The process proceeds to step S25. If it is determined in step S22 that the discharge roller 53 does not pinch the residual sheet S2, the control unit 70 drives the guide member 55 to guide the residual sheet S2 to the reverse conveyance path 54 (step S24). ), And proceeds to step S25. At this time, the control unit 70 drives the conveyance rollers 46 and 57, for example, to convey the residual sheet S2 until at least the rear end of the residual sheet S2 passes through the boundary B2.

  In this way, as shown in FIG. 3D, the residual sheets S1, S2, S3, S4 are conveyed so as not to straddle the boundary portions B1, B2, B3, B4, respectively, and the residual sheets S1, It is possible to prevent S2, S3, and S4 from interfering when the drawer unit 80 is pulled out. In particular, the residual sheet S1 remaining on the upstream side in the conveyance direction of the registration roller is stored in the residual sheet storage portion 81 when the leading end of the residual sheet S1 is upstream in the conveyance direction of the guide member 82. When the leading edge of the residual sheet S1 is downstream in the conveyance direction of the guide member 82, the registration roller 19 and the roller downstream in the conveyance direction from the registration roller 19 are stopped and the trailing edge of the residual sheet S1 is stopped. Is carried out. Accordingly, for example, the residual sheet S1 is conveyed to a position where it does not straddle the boundary portion B1 without colliding with the jammed sheet SJ in the vicinity of the fixing unit 42. Therefore, when the drawer unit 80 is pulled out, the residual sheet S1 is broken. Thus, it is possible to prevent a piece of paper from remaining in the apparatus. Further, since the residual sheet S1 is not conveyed to the nip portion 45 where the unfixed toner is adhered, it is possible to prevent the residual sheet S1 from being contaminated by scattering of the toner into the apparatus. .

  Then, the control unit 70 displays on the operation display panel 90 that there is a jammed sheet and a remaining sheet in the printer 1 (step S25). Thereby, it is possible to prompt the user to perform jam processing on the sheet.

  By the above-described jam processing control, the user can set the jam sheets SJ and the remaining sheets S1, S2, S3, and S4 in a state where the remaining sheets S1, S2, S3, and S4 do not straddle the boundary portions B1, B2, B3, and B4. Perform removal work. Specifically, the user refers to the display on the operation display panel 90 and pulls out the drawer unit 80 or opens a plurality of doors (not shown) provided on the side surface of the printer 1 to access the jammed sheet and the remaining sheet. And remove them. The user can comfortably perform the jam processing because the sheet is not broken even if the sheet is removed from an arbitrary place among the plurality of doors and the drawer unit 80.

  Further, when the residual sheet S1 is detected in the residual sheet storage unit 81 by the stack detection unit 83, the control unit 70 displays the presence of the residual sheet S1 on the operation display panel 90. Thereby, it is possible to prevent forgetting to remove the remaining sheet S1. The front side of the residual sheet storage unit 81 operated by the user may be transparent so that the user can easily see the residual sheet S1 in the residual sheet storage unit 81.

  As described above, in the present exemplary embodiment, an example of the jam processing control when the jam sheet SJ causes a jam between the nip portion 45 and the fixing portion 42 has been described. Even when the jam sheet SJ is jammed at a position other than between the nip portion 45 and the fixing portion 42, the sheet remaining in the printer 1 is conveyed in the same manner as in the above-described jam processing control. The same effect as the embodiment can be obtained.

  The drawer unit 80 is configured such that the registration roller 19, the nip portion 45, the pre-fixing conveyance device 41, the fixing portion 42, the double-sided conveyance path 20, and the like can be integrally drawn. It may be configured to be able to be drawn out in a form divided into two.

  Further, instead of the residual sheet detection unit SN5 arranged upstream in the conveyance direction of the registration roller 19, as shown in FIG. 6, the residual sheet detection unit SN51 downstream of the registration roller 19 and upstream of the guide member 82 in the conveyance direction. May be arranged. In step S13 described above, based on the detection result of the residual sheet detection unit SN51, the control unit 70 determines whether the position of the leading end of the residual sheet S1 is upstream of the guide member 82 in the transport direction. If it is determined that the position of the leading edge of the remaining sheet S1 is upstream of the guide member 82 in the transport direction, the process proceeds to step S14, and the position of the leading edge of the residual sheet S1 is downstream of the guide member 82 in the transport direction. If it is determined, the process proceeds to step S24. Accordingly, the control unit 70 can more accurately determine whether or not the remaining sheet S1 can be guided to the remaining sheet storage unit 81.

  Further, the guide member 82 and the remaining sheet detection unit SN51 may be arranged on the upstream side of the registration roller 19 and the downstream side of the boundary portion B1 in the transport direction. Even in this case, the control unit 70 determines whether the position of the leading end of the remaining sheet S1 is on the upstream side or the lower side in the conveyance direction of the guide member 82 based on the detection result of the residual sheet detection unit SN51. The guide member 82 is controlled. In addition, a shutter member configured to be able to rotate while rotating in contact with the leading end of the sheet to correct the skew of the sheet is provided upstream of the registration roller 19 in the conveyance direction.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. However, with respect to the same configuration as that of the first embodiment, the illustration is omitted or the same reference numerals are given to the drawings and the description is omitted. As shown in FIG. 7, the printer 100 includes a printer main body 1 </ b> A and a drawer unit 180. The drawing unit 180 is configured so that the registration roller 19, the nip portion 45, the pre-fixing conveyance device 41, the fixing portion 42, the double-sided conveyance path 20, and the like can be drawn from the printer 100.

  Above the pre-registration roller 18 and the registration roller 19, a residual sheet storage portion 181 for storing the residual sheet S1 is disposed in the printer main body 1A. A guide member 182 is disposed downstream of the registration roller 19 in the conveyance direction. The guide member 182 alternatively guides the residual sheet S1 that has passed through the registration roller 19 to the nip portion 45 and the residual sheet storage portion 181.

  Since the present embodiment is configured as described above, the remaining sheet storage portion 181 is disposed not in the drawer unit 180 but in the printer main body 1A, and the drawer unit 180 can be downsized to improve operability. .

  Note that in the jam processing control of the present embodiment, the guide member 82 and the residual sheet storage portion 81 of the first embodiment correspond to the guide member 182 and the residual sheet storage portion 181 of the present embodiment, respectively. 4 and FIG. 5 is not different from the jam processing control. Therefore, description of jam processing control is omitted.

1: Printer (image forming apparatus), 1A: Printer main body (apparatus main body), 14, 15, 16, 17, 21, 22, 23, 46, 57, 58, 59, 60, 61: Conveying rollers (conveying means) , 18: Roller before registration (conveying means), 19: Registration roller (skew correction means, conveying means), 45: Nip part (image forming means), 70: Control part (control means), 80, 180: Drawer Unit (drawing means), 81: residual sheet storage section (storage means), 82: guide member (guide means), B1: boundary, SN1: residual sheet detection section (residual sheet detection means), SN5: residual sheet detection section (Lead edge detection means) S1: Residual sheet

Claims (8)

A skew feeding correcting means for correcting the skew feeding of the sheet, and a transport means for transporting the sheet;
Image forming means for forming an image on the sheet conveyed by the conveying means;
In order to remove the sheet in the apparatus, drawer means that can be pulled out in a pull-out direction orthogonal to the sheet conveying direction;
A residual sheet detecting means for detecting a residual sheet remaining across a boundary portion between the drawing means and the apparatus main body upstream of the skew feeding correcting means in the transport direction when a sheet jam occurs; ,
Storage means for storing the residual sheet;
Guiding means for selectively guiding the residual sheet to the image forming means and the storage means;
Leading edge detection means for detecting the position of the leading edge of the residual sheet in the transport direction;
The residual sheet detecting means detects the residual sheet, and based on the detection result of the leading edge detecting means, it is determined that the leading edge of the residual sheet in the conveying direction is upstream of the guiding means in the conveying direction. Control means for controlling the guide means so that the residual sheet is guided to the storage means, and for controlling the transport means so that the residual sheet is transported to the storage means,
An image forming apparatus. When the control means determines that the leading edge of the remaining sheet in the transport direction has reached the guide means based on the detection result of the leading edge detection means, the control means stops driving the skew feeding correction means, Controlling the conveying means so that a rear end of the remaining sheet in the conveying direction passes through the boundary portion;
The image forming apparatus according to claim 1. A skew feeding correcting means for correcting the skew feeding of the sheet, and a transport means for transporting the sheet;
Image forming means for forming an image on the sheet conveyed by the conveying means;
In order to remove the sheet in the apparatus, drawer means that can be pulled out in a pull-out direction orthogonal to the sheet conveying direction;
A residual sheet detecting means for detecting a residual sheet remaining across a boundary portion between the drawing means and the apparatus main body upstream of the skew feeding correcting means in the transport direction when a sheet jam occurs; ,
Storage means for storing the residual sheet;
Guidance means for alternatively guiding the residual sheet that has passed through the skew feeding correction means to the image forming means and the storage means;
Leading edge detection means for detecting the position of the leading edge of the residual sheet in the transport direction;
When the residual sheet detection unit detects the residual sheet and determines, based on the detection result of the front end detection unit, that the front end of the residual sheet in the transport direction has reached the skew feeding correction unit, Control means for controlling the conveying means so that the trailing edge of the residual sheet in the conveying direction passes through the boundary portion while stopping the driving of the row correcting means,
An image forming apparatus. When the control means determines that the leading edge of the remaining sheet in the transport direction has reached the skew correction means based on the detection result of the leading edge detection means, the drive of the skew correction means is stopped. Controlling the conveying means so that a rear end of the residual sheet in the conveying direction passes through the boundary portion;
The image forming apparatus according to claim 3. A fixing unit for fixing the image formed on the sheet in the image forming unit;
The drawing unit is configured to be able to pull out the skew feeding correction unit, the image forming unit, and the fixing unit in the drawing direction,
Fixing residual sheet detecting means for detecting a fixing residual sheet remaining across the fixing boundary between the drawing means and the apparatus main body on the downstream side of the fixing means in the transport direction when a sheet jam occurs. With
When the fixing residual sheet detection unit detects the fixing residual sheet, the control unit controls the conveying unit so that the fixing residual sheet is conveyed to a position that does not straddle the fixing boundary portion.
The image forming apparatus according to claim 1. The conveying unit includes a reversing unit that reverses the sheet that has passed through the image forming unit, and a double-sided conveying unit that receives the sheet reversed by the reversing unit and conveys the sheet to the image forming unit.
The drawer unit is configured to be able to pull out the skew feeding correction unit, the image forming unit, the fixing unit, and the double-sided conveyance unit in the drawing direction,
Double-sided residual sheet detection for detecting a double-sided residual sheet remaining across a double-sided boundary between the drawing unit and the apparatus main body on the upstream side of the double-sided conveyance unit in the conveyance direction when a sheet jam occurs With means,
When the double-sided residual sheet detection unit detects the double-sided residual sheet, the control unit controls the conveyance unit so that the double-sided residual sheet is conveyed to a position that does not straddle the double-sided boundary part.
The image forming apparatus according to claim 5. Sheet stacking means on which sheets are stacked;
A feeding means for feeding sheets from the sheet stacking means,
The double-sided conveying unit is configured to guide the sheet to the image forming unit while feeding the sheet from the feeding unit.
When a sheet jam occurs, the sheet is fed to detect a sheet remaining in the feeding direction, remaining on the downstream side of the feeding unit in the transport direction and straddling the feeding boundary between the drawing unit and the apparatus main body. With residual sheet detection means,
The control means controls the conveying means so that the fed residual sheet is conveyed to a position not straddling the feeding boundary when the fed residual sheet detecting means detects the fed residual sheet. ,
The image forming apparatus according to claim 6. The storage means is provided in the drawer means.
The image forming apparatus according to claim 1.

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