JP2006248772A - Sheet processing apparatus and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve alignment accuracy on a processing tray when a large sheet such as a legal size is laterally fed.
When aligning sheets P on a stacking surface 24a of a processing tray 24, a first alignment mode or a second alignment mode is selected. In the first alignment mode, the rear end P1 of the sheet P is abutted against the rear end reference plate 34 by the vertical paddle 36, the side end P4 is pushed by the horizontal alignment plate 39, and the side end P2 is pushed to the side end reference plate 35. It is a thing to guess. In the second alignment mode, the side edge P2 of the sheet P is abutted against the side edge reference plate 35 by the horizontal paddle 37, the leading edge P3 is pressed by the vertical alignment plate 38, and the trailing edge P1 is pressed against the trailing edge reference plate 34. Is. In the case of the legal size sheet P, the alignment accuracy can be improved by bringing the side edge P2 having the long side into contact with the side edge reference plate 35.
[Selection] Figure 10

Description

  The present invention relates to a sheet processing apparatus for aligning sheets and an image forming apparatus including the sheet processing apparatus.

  In the sheet processing apparatus described in Patent Document 1, when aligning sheets on a processing tray, one end (for example, the rear end) in the sheet conveying direction is abutted against the trailing end stopper, thereby conveying the sheet. Position correction in the direction, so-called alignment was performed. The alignment in the sheet width direction is performed by jogging one side end in the sheet width direction and abutting the other side end against the abutting member.

  The sheet processing apparatus will be described with reference to FIGS. 12, 13, and 14. FIG. The sheet P conveyed to the sheet processing apparatus after the image formation is conveyed by the entrance roller 121 and the conveyance roller 122, and is discharged and stacked on the processing tray 124 by the paper discharge roller 123. The stacked sheets are conveyed toward the rear end stopper 134 by the counterclockwise rotation of the paddle 136 in FIG. 12, and the rear end P1 shown in FIG. Thereby, alignment in the conveyance direction (sheet conveyance direction) is performed. Further, the sheet P stacked on the processing tray 124 has one side end P4 pushed (jogged) toward the abutting plate 135 by the side regulating plate 139, so that the other side end P2 has the abutting plate. It is abutted to 135. Thereby, alignment in the width direction (sheet width direction) is performed. A state in which a plurality of sheets P (sheet bundles) are aligned on the processing tray 124 by repeating the above-described alignment in the transport direction and the width direction with respect to the sheets P sequentially discharged onto the processing tray 124. Stacked in. Thereafter, the sheet bundle is nipped and conveyed by the rollers 126, 127, and 128 supported by the swing guide and the rollers 129, 130, and 131 on the processing tray 124 as the swing guide 125 is lowered. The paper is discharged onto the stacking tray 132.

Japanese Patent Laid-Open No. 10-181981

However, in the above-described sheet processing apparatus, the rear end P1 of the sheet P may float not only from the rear end stopper 134 but also from the rear end stopper 134. Here, as shown in FIG. 15, a case is considered in which the sheet P is A4 size (long side × short side = 297 mm × 210 mm) and the long side becomes the rear end P1 and is abutted against the rear end stopper 134. In this case, when one of the rear ends P1 floats, for example, by 0.5 mm, the front end P4 shifts to the position Pb with respect to the normal position Pa. At this time, the shift amount in the sheet width direction at the end of the front end P4 is 0.61 mm (= (0.5 ² + (0.5 × 210/297) ² ) ^1/2 ) and 0.5 mm at the maximum. Almost no change.

On the other hand, as shown in FIGS. 16 and 17, the rear end P <b> 1 that abuts against the rear end stopper 134 such as a sheet P having a legal size (long side × short side = 355.6 mm × 215.9 mm) has a short side. In some cases, when one end of the rear end P1 is lifted 0.5 mm from the rear end stopper 134, the end of the front end P1 is shifted from the normal position Pa to the position Pb. The displacement amount at this time is a maximum of 0.96 mm (= (0.5 ² + (0.5 × 355.6 / 215.9) ² ) ^1/2 ), which is almost twice as large as 0.5 mm. There is a problem that the accuracy of matching is lowered.

  SUMMARY An advantage of some aspects of the invention is that it provides a sheet processing apparatus capable of aligning sheets on a processing tray with high accuracy and an image forming apparatus including the sheet processing apparatus.

  The present invention relates to a sheet processing apparatus for aligning sheets conveyed to a processing tray, a first reference member against which a first sheet end perpendicular to the sheet conveying direction of the sheet conveyed to the processing tray is abutted, A second reference member against which a second sheet end parallel to the sheet conveying direction is abutted; and a third sheet end parallel to the first sheet end to push the first sheet end A first alignment member that abuts against the first reference member and a fourth sheet end parallel to the second sheet end are pushed to abut the second sheet end against the second reference member. And a second alignment member.

  According to the present invention, alignment operations can be performed on sheets conveyed on the processing tray with reference to sheet end portions orthogonal to each other. That is, for example, in the case of a general rectangular sheet having a long side and a short side, the alignment operation can be performed with reference to the long side regardless of the discharge direction on the stacking tray. As described in detail in the embodiment, it is possible to perform alignment with high alignment accuracy.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, what attached | subjected the same code | symbol in the same drawing or a different drawing performs the same structure or the same effect | action, The duplication description is abbreviate | omitted suitably about these.

<Embodiment 1>
FIG. 1 shows an image forming apparatus to which the present invention can be applied. The image forming apparatus shown in FIG. 1 is an electrophotographic copying machine 100, which is viewed from the front side, that is, the side where a user or a service person is located when operating the copying machine 100. It is a schematic diagram corresponded to a longitudinal cross-sectional view.

  The outline of the configuration and operation of the copying machine 100 will be described with reference to FIG.

  The copying machine 100 includes a copying machine main body 1 having a substantially box shape.

  An automatic document feeder (ADF) 2 is mounted on the upper surface of the copying machine main body 1, and a sheet processing device 3 is mounted on the left side surface. The sheet processing apparatus 3 may be detachably attached to the copying machine main body 1 as an option, for example, or may be integrated into a frame (not shown) of the copying machine main body 1. Inside the copying machine main body 1, a sheet feeding / conveying unit 4 is provided at the lower part, and an image forming unit 5 is provided at the upper part. Further, a fixing unit 6 is provided on the left side of the image forming unit 5, and a sheet refeeding unit 7 is provided below the fixing unit.

  The automatic document feeder 2 is disposed so as to cover a transparent document glass (not shown) disposed on the upper surface of the copying machine main body 1. A document (not shown) set on the automatic document feeder 2 is carried onto the platen glass by the automatic document feeder 2 and placed at a document reading position (not shown) with the image surface facing downward. Placed. The document is read from the image information on the image plane by an image reading unit (not shown). The document after reading is unloaded from the reading position by the automatic document feeder 2 and removed. When there are a plurality of documents, the above-described loading, placing, and unloading operations are sequentially repeated for each document.

  The sheet processing apparatus 3 will be described in detail later.

  The sheet feeding / conveying unit 4 feeds and conveys the sheet P and supplies it to an image forming unit 5 described below.

  The image forming unit 5 includes a photosensitive drum 11, a charger 12, an exposure device 13, a developing device 14, a transfer charge, which are arranged around the photosensitive drum 11 around the photosensitive drum 11 from the upstream side in the rotation direction (clockwise). A container 15, a cleaner 16, and the like. The charger 12 uniformly charges the surface of the photosensitive drum 11. The exposure device 13 exposes the surface of the charged photosensitive drum 11 with a laser beam L that is on / off controlled based on image information read by the image reading unit. Thereby, the electric charge of the exposed part is removed, and an electrostatic latent image is formed on the surface of the photosensitive drum 11. The developing device 14 attaches toner (developer) to the electrostatic latent image and develops the electrostatic latent image as a toner image. The toner image thus formed on the photosensitive drum 11 is conveyed to a transfer portion between the photosensitive drum 11 and the transfer charger 15 as the photosensitive drum 11 rotates in the arrow direction. The transfer charger 15 transfers the toner image on the photosensitive drum 11 conveyed to the transfer unit onto the sheet P supplied to the transfer unit by the sheet feeding / conveying unit 4. After the toner image is transferred, the toner (transfer residual toner) remaining on the surface of the photosensitive drum 11 is removed by the cleaner 16 and used for the next image formation starting from charging.

  The fixing unit 6 heats and pressurizes the toner image transferred onto the sheet P by the image forming unit 5 to fix it on the surface of the sheet P. The sheet P after the toner image is fixed is discharged toward the sheet processing apparatus 3 by the paper discharge roller 17. Thereby, the image formation on the surface (one side) of one sheet P is completed. When an image is also formed on the back surface of the sheet P, the sheet P having a toner image fixed on the front surface is guided to the lower sheet refeed unit 7 and is turned upside down. It is supplied to the image forming unit 5. This is the end of the description of the overall configuration and operation of the copying machine 100.

  Next, the sheet processing apparatus 3 to which the present invention can be applied will be described in detail.

  FIG. 2 shows a view of the sheet processing apparatus as viewed from the front side. FIG. 3 shows a view of the vicinity of the processing tray 24 from above.

  As shown in these drawings, the sheet processing apparatus includes a rear end reference plate (first reference member) against which a sheet transport direction rear end (first sheet end) P1 of the sheet transported to the processing tray 24 is abutted. ) 34, a side end reference plate (second reference member) 35 against which a side end (second sheet end) P2 perpendicular to the rear end P1 of the sheet P on the stacking surface 24a abuts, and the stacking surface 24a. A vertical alignment plate (first alignment member) 38 that pushes the front end (third sheet end) P3 parallel to the rear end P1 of the upper sheet P to abut the rear end P1 against the rear end reference plate 34, and a stacking surface A lateral alignment plate (second alignment member) 39 that presses another side end (fourth sheet end) P4 parallel to the side end P2 of the sheet P on the sheet 24a and abuts the side end P2 against the side end reference plate 35. And as a main component.

  As shown in FIG. 1, on the copier body 1 side above the processing tray 24, an entrance roller 21 for receiving the sheet P discharged from the paper discharge tray 17 of the copier body 1, and a transport roller for transporting the sheet P 22. A paper discharge roller 23 for discharging the sheet P onto the stacking surface 24a of the processing tray 24 is disposed. Further, above the processing tray 24, a vertical paddle 36 that feeds the sheet P on the stacking surface 24a so that the rear end P1 contacts the rear end reference plate 34, and the sheet P on the stacking surface 24a A horizontal paddle 37 is disposed so that P2 contacts the side end reference plate 35. Further, a guide member 25 that can be raised and lowered is disposed above the processing tray 24, and bundle discharge rollers 26, 27, and 28 are rotatably supported by the lift guide. These bundle paper discharge rollers 26, 27, 28 are connected to the rollers 29, 30, 31 disposed on the stacking surface 24 a of the processing tray 24 when the lifting guide 25 is lowered and disposed at the closed position. A sheet bundle is sandwiched between the sheets and discharged onto the stacking tray 32.

  2, the rear end reference plate 34 is supported by a shaft 34b so as to be swingable. When the sheets P are aligned, the reference surface 34a (see FIG. 3) is perpendicular to the stacking surface 24a. Located in. On the other hand, when staple processing is performed by the stapler 33 after the sheet bundle on the stacking surface 24a is aligned, the operation of the stapler 33 is not hindered by retracting below the stacking surface 24. The side end reference plate 35 is arranged so that its reference surface 35a is perpendicular to the stacking surface 24a, and moves according to the size of the sheets P stacked on the stacking surface 24a. . Further, the rear end reference plate 34 and the side end reference plate 35 are arranged such that the respective reference surfaces 34a and 35a are perpendicular to each other.

  The vertical alignment plate 38 facing the rear end reference plate 34 reciprocates in a direction approaching and separating from the rear end reference plate 34 by a driving means (not shown). The lateral alignment plate 39 facing the side end reference plate 35 reciprocates in a direction approaching and separating from the side end reference plate 35 by a driving means (not shown). The vertical alignment plate 38 can be retracted below the stacking surface as shown in FIG.

  The entire processing tray 24 is supported by a base plate 41 so that the vertical alignment plate 38 side can swing substantially vertically with respect to a shaft 40 provided at a lower portion on the rear end reference plate 34 side. . Between the base plate 41 and the processing tray 24, a first angle control mechanism (first alignment assisting means) 43 for adjusting the inclination angle of the processing tray 24 is disposed. The angle control mechanism 43 includes a motor 43a mounted on the base plate 41 and an arm 43b that is swung by the motor 43a. The tip of the arm 43b slides with respect to the lower surface of the processing tray 24. By controlling the rotation angle of the motor 43a, the tilt angle of the arm 43b and further the tilt angle of the processing tray 24 can be controlled. This control is performed by the control means 45 shown in FIG.

  Further, as shown in FIG. 4, a second angle control mechanism (second alignment assisting means) 44 that is substantially the same as the first angle control mechanism 43 described above is mounted on the base plate 41 as well. . That is, the sheet processing apparatus is arranged so that the base plate 41 can swing substantially in the vertical direction on the side of the lateral alignment plate 39 with reference to the shaft 42 provided on the lower side of the side end reference plate 35 of the processing tray 24. 3 is supported by a part 3a of the apparatus main body. Between the part 3a of the apparatus main body and the base plate 41, a second angle control mechanism 44 for adjusting the inclination angle of the base plate 41 is disposed. The angle control mechanism 44 includes a motor 44a mounted on a part 3a of the apparatus main body and an arm 44b that is swung by the motor 44a. The tip of the arm 44b slides with respect to the lower surface of the base plate 41. By controlling the rotation angle of the motor 44a, the tilt angle of the arm 44b and further the tilt angle of the base plate 41 can be controlled. This control is performed by the control means (control unit) 45 shown in FIG. Here, the control means 45 controls the overall operation of the sheet processing apparatus 3 based on signals from various sensors (not shown) .In FIG. Although an example provided in the apparatus 3 is illustrated, the present invention is not limited to this, and control means (on the copying machine main body 1 side for controlling the operation of the entire copying machine main body 1) The operation of the entire sheet processing apparatus 3 may be controlled by an unillustrated).

  By the operations of the first angle control mechanism 43 and the second angle control mechanism 44, the stacking surface 24 a on the processing tray 24 has a posture in which the rear end reference plate 34 side is inclined downward with respect to the horizontal plane, and is also in the horizontal plane. On the other hand, a posture in which the side end reference plate 35 side is inclined downward and a posture in which the rear end reference plate 34 side is inclined downward with respect to the horizontal plane and a posture in which the side end reference plate 35 side is inclined downward are selectively taken. be able to.

  The sheet processing apparatus configured as described above operates as follows. In the following description, the operation of aligning the sheets P on the stacking surface 24a using the rear end reference plate 34, the side end reference plate 35, and the lateral alignment plate 39 is referred to as a first alignment operation (first operation). : First alignment mode), and the alignment operation using the rear end reference plate 34, the side end reference plate 35 and the vertical alignment plate 38 is the second alignment operation (second operation: second alignment mode). Mode). The control means 45 selects whether to perform the first alignment operation or the second alignment operation.

  First, as shown in FIG. 9, signals relating to the size of the sheet P and the feeding direction (longitudinal feeding or lateral feeding) of the sheet P are input from the copying machine body 1 to the control unit 45. The control unit 45 determines whether the first matching operation or the second matching operation is performed based on the input signal. When the sheet P is A4 size and is laterally fed, as shown in FIGS. 5 and 6, the rear end P <b> 1 of the sheet P that is in contact with the rear end rear end reference plate 34 is a long side. The side end P2 in contact with the side end reference plate 35 is a short side. That is, since the rear end P1 is longer than the side end P2, the rear end reference plate 34 becomes the reference for alignment.

  Therefore, the control means 45 retracts the vertical alignment plate 38 that is not used, and moves the side end reference plate 35 and the horizontal alignment plate 39 outside a predetermined amount (for example, 10 mm) from the end of the A4 size sheet. In parallel with this, as shown in FIG. 8, the entire processing tray 24 is swung around the shaft 40 by the first angle control mechanism 43, and the stacking surface 24 a is on the rear end reference plate 34 side. To tilt. Next, the sheet discharged from the copying machine main body 1 is discharged onto the stacking surface 24 a of the processing tray 24 by the entrance roller 21, the transport roller 22, and the paper discharge roller 23. The vertical paddle 36 is actuated on the discharged sheet P, and the sheet P is aligned with the trailing edge P1 abutting against the trailing edge reference plate 34. Next, the side end P4 of the sheet P is pushed by the lateral alignment plate 39 and the side end P2 is abutted against the side end reference plate 35. Then, the same operation is repeated, and when a predetermined number of sheets P are aligned, as shown in FIG. 7, the trailing end reference plate 34 is retracted, and the stapler 33 approaches the sheet bundle to perform the stapling process. Do. Thereafter, as shown in FIG. 8, together with the lifting guide 25 (see FIG. 5), the bundle discharge rollers 26, 27, and 28 are lowered, and the sheet bundle is sandwiched between the rollers 29, 30, and 31. The bundle is discharged onto the stacking tray 32.

Next, as shown in FIGS. 4 and 10, when the sheet S is legal size and vertically fed, the sheet P has a short side at the rear end P <b> 1 that contacts the rear end reference plate 34, and the side end reference plate. The side end P <b> 2 in contact with 35 is a long side. In this case, the reference for alignment is the side end reference plate 35. Therefore, the control means 45 moves the side end reference plate 35 and the vertical alignment plate 38 out of a certain amount (for example, 10 mm) from the end of the legal size sheet. In parallel with this, the entire processing tray 24 and the base plate 41 are swung around the shaft 42 by the second angle control mechanism 44 so that the stacking surface 24a is on the side end reference plate 35 side. Tilt. Next, the sheet P discharged from the copying machine main body 1 is discharged onto the stacking surface 24 a of the processing tray 24 by the entrance roller 21, the transport roller 22, and the paper discharge roller 23. The lateral paddle 37 is actuated on the discharged sheet P, and the sheet P is aligned with the side end P2 being abutted against the side end reference plate 35. Next, the front end P3 of the sheet P is pushed by the vertical alignment plate 38, and the rear end P1 is abutted against the rear end reference plate 34. Then, the same operation is repeated, and when a predetermined number of sheets P are aligned, as shown in FIG. 7, the trailing end reference plate 34 is retracted, and the stapler 33 approaches the sheet bundle to perform the stapling process. Do. Thereafter, as shown in FIG. 8, the bundle discharge rollers 26, 27, and 28 are lowered together with the lifting guide 25, and the sheet bundle is sandwiched between the rollers 29, 30, and 31. Drain up. Since the side end reference plate 35 is used for the legal size sheet P and alignment is performed on the long side which is the side end of the sheet P, alignment can be performed with high accuracy. As shown in FIG. 11, in comparison with the conventional example of FIG. 17, in the present embodiment, the sheet end of the side end P1 floats 0.5 mm from the side end reference plate 35 with respect to the legal position. The maximum deviation from the rear reference plate 34 is 0.58 mm ((0.5 ² + (0.5 × 215.9 / 355.6) ² ) ^1/2 ), which is 0.5 mm. It becomes almost untouched.

1 is a schematic view of a configuration of an image forming apparatus to which the present invention can be applied as viewed from the front side. It is the figure which looked at the processing tray vicinity from the front side. It is the figure which looked at the processing tray vicinity from upper direction. It is the figure which looked at the processing tray of the state made to incline from the left in FIG. It is the figure which looked at the process tray of the state made to incline from the front side. It is the figure which looked at aligning the sheet | seat of A4 size from upper direction. FIG. 5 is a view of a stapled sheet bundle on a processing tray as viewed from the front side. FIG. 6 is a view of a sheet bundle after stapling as viewed from the front side to be discharged toward a stacking train. It is a figure explaining the 1st matching operation and the 2nd matching operation. It is the figure which looked at aligning a legal size sheet from the upper part. It is a figure explaining the effect at the time of applying the present invention to a legal size sheet. It is the figure which looked at the conventional processing tray vicinity from the front side. It is the figure which looked at the conventional process tray vicinity from the upper direction. It is the figure which looked at aligning A4 size sheet on the conventional processing tray from the upper part. It is a figure explaining the conventional deviation | shift amount in an A4 size sheet. It is the figure which looked at aligning a legal size sheet | seat on the conventional processing tray from upper direction. It is a figure explaining the conventional deviation | shift amount in a legal size sheet | seat.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Copier main body 3 Sheet processing apparatus 5 Image forming part 24 Processing tray 24a Loading surface 34 Rear end reference plate (first reference member)
35 Side end reference plate (second reference member)
38 Vertical alignment plate (first alignment member)
39 Lateral alignment plate (second alignment member)
43 First angle control mechanism (first alignment assisting means)
44 Second angle control mechanism (second alignment assisting means)
45 Control means 100 Copying machine (image forming apparatus)
P sheet P1 rear end (first sheet end)
P2 side edge (second sheet edge)
P3 tip (third sheet edge)
P4 side edge (fourth sheet edge)

Claims (6)

In a sheet processing apparatus for aligning sheets conveyed to a processing tray,
A first reference member against which a first sheet end perpendicular to the sheet conveyance direction of the sheet conveyed to the processing tray is abutted;
A second reference member against which a second sheet end parallel to the sheet conveying direction is abutted;
A first alignment member that presses a third sheet end parallel to the first sheet end to abut the first sheet end against the first reference member;
A second alignment member that presses a fourth sheet end parallel to the second sheet end and abuts the second sheet end against the second reference member;
A sheet processing apparatus. A first alignment mode in which sheets on the processing tray are aligned by the first reference member, the second reference member, and the second alignment member; and the first reference member and the second reference Control means for executing a second alignment mode for aligning sheets on the processing tray by a member and the first alignment member;
The sheet processing apparatus according to claim 1. First alignment assisting means for applying a force toward the first reference member to the sheet on the processing tray when the first alignment mode is executed;
Second alignment assisting means for applying a force toward the second reference member to the sheet on the processing tray when the second alignment mode is executed.
The sheet processing apparatus according to claim 2. When aligning a sheet having a long side and a short side, the control means executes the first alignment mode when the long side is abutted against the first reference member, and the long side is Executing the second alignment mode when abutted against the second reference member;
The sheet processing apparatus according to claim 2, wherein the sheet processing apparatus is a sheet processing apparatus. The first alignment assisting means can change a relative height of the stacking surface on the first reference member side, and the first reference on the stacking surface is executed when the first alignment mode is executed. Inclining the stacking surface so that the member side is lower,
The second alignment assisting means can change the relative height of the stacking surface on the second reference member side, and when the second alignment mode is executed, Inclining the stacking surface so that the reference member side is lowered,
The sheet processing apparatus according to claim 3, wherein the sheet processing apparatus is provided. An image forming apparatus comprising: an image forming unit that forms an image on a sheet; and a sheet processing device that aligns a sheet on which an image is formed by the image forming unit.
The sheet processing apparatus is a sheet processing apparatus according to any one of claims 1 to 5.
An image forming apparatus.

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