JP2004284773A - Paper loading device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To deliver a paper onto a delivery tray with satisfactory attitude even when swelling and curl due to a binding staple exist on the paper delivered on the delivery tray. <P>SOLUTION: This paper loading device is provided with the delivery tray delivering the paper on which image is formed in a loaded condition and pressing members pressing a rear end part in the direction of delivery of the paper delivered on the delivery tray. A plurality of pressing members are arranged along the direction orthogonal for the direction of delivery of paper and are energized to press the paper delivered on the delivery tray individually. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a paper stacking apparatus that stacks paper on which an image is formed by an image forming apparatus such as a copier, a printer, a facsimile, or a multifunction peripheral of the electrophotographic system, and more particularly, to a paper stack on which an image is formed. The present invention relates to a sheet stacking device suitably used in combination with a post-processing device that performs post-processing.
[0002]
[Patent Document 1] Japanese Patent Application Laid-Open No. 2002-87685 [Patent Document 2] Japanese Patent Application Laid-Open No. 10-250897 [0003]
[Prior art]
Conventionally, an image forming apparatus such as a copier, a printer, a facsimile, or a multifunction peripheral of these types that employs this type of electrophotographic method, binds a sheet on which an image is formed, performs perforation processing on the sheet, Alternatively, a sheet on which an image is formed is discharged in a state where the sheets are offset (shifted) one set at a time, and thus the sheet is sometimes used in combination with a sheet post-processing apparatus including a stapler, a puncher, or an offset catch tray. . The sheet post-processing apparatus uses a sheet stacking apparatus that discharges stapled sheets, perforated sheets, and the like in a stacked state using a stapler, a puncher, or the like.
[0004]
Various technologies relating to the paper stacking device have been already proposed and commercialized. For example, there is a technology disclosed in Japanese Patent Application Laid-Open No. 2002-87685.
[0005]
The paper discharge device of the image forming apparatus according to Japanese Patent Application Laid-Open No. 2002-87685 provides a paper discharge device of the image forming apparatus capable of aligning the discharge sheets on a discharge tray by eliminating a sheet shift due to discharge of a subsequent sheet. Therefore, in a paper discharge device of an image forming apparatus, comprising: a movable paper discharge tray; and an actuator that contacts a top surface of the paper discharged to the movable paper discharge tray to detect fullness and an upper-lower upper-limit position. The actuator is disposed so as to be capable of coming into contact with and separating from the sheet placement surface of the movable discharge tray or the upper surface of the sheet discharged to the movable tray, and has been discharged to the movable discharge tray during continuous discharge. It is configured to be also used as a paper upper surface pressing means.
[0006]
However, in the case of the sheet discharge device of the image forming apparatus according to Japanese Patent Application Laid-Open No. 2002-87685, an actuator that detects the fullness and the upper / lower upper limit position by contacting the upper surface of the sheet discharged to the movable discharge tray is provided. During continuous discharge, the paper discharge device is configured to also serve as a paper upper surface pressing means for pressing the upper surface of the paper discharged to the movable discharge tray, but since only one actuator is provided, When the succeeding sheet bundle is discharged onto the discharge tray, the sheets already stacked by the discharged sheet bundle rotate around the actuator as a fulcrum, and the posture of the discharged sheet is disturbed. have.
[0007]
Thus, as a technique relating to a paper stacking apparatus in which such a problem is unlikely to occur, for example, there is a technique disclosed in Japanese Patent Application Laid-Open No. 10-250897.
[0008]
The paper processing apparatus according to Japanese Patent Application Laid-Open No. H10-250897 discloses a bin for stacking sheets discharged from an image forming apparatus, a loading tray installed above the bin, which can load a large amount of sheets, A sheet bundle conveying means for conveying the upper sheet bundle upward and storing the sheet bundle in the stacking tray; and a sheet already stored in the stacking tray when the sheet bundle is stored on the stacking tray by the sheet bundle conveying means. And a pressing member for pressing the upper surface of the rear end portion of the bundle. The plurality of holding members are attached to the rotating shaft while being fixed.
[0009]
[Problems to be solved by the invention]
However, the prior art has the following problems. That is, in the case of the paper processing apparatus according to the above-mentioned Japanese Patent Application Laid-Open No. 10-250897, a plurality of pressing members fixed to the rotating shaft press the staples of the stapled bundle of paper sheets so as to suppress the bulge. However, since the plurality of pressing members are fixed to the rotating shaft, if one pressing member is in contact with the swelling of the sheet bundle, the other pressing members float and the swelling remains in the sheet bundle. Also, there is a problem that the rotation of the sheet bundle cannot be reliably prevented.
[0010]
Further, in the case of the paper processing apparatus according to the above-described Japanese Patent Application Laid-Open No. 10-250897, in addition to the swelling of the staples of the bound sheet bundle, if the sheet is curled, In some cases, the pressing member comes into contact with only one place, and the rotation of the sheet bundle cannot be surely prevented, and there is a problem that the posture of the discharged sheet is disturbed.
[0011]
Further, in the case of the paper processing apparatus disclosed in Japanese Patent Application Laid-Open No. 10-250897, since the pressing member only performs the operation of pressing the paper when discharging the paper, the paper is discharged onto the discharge tray depending on the state of the curl of the paper. At the base end of the discharged paper, the paper is left floating due to the curl remaining at both ends in the direction orthogonal to the discharge direction, and the discharged paper or the bundle of paper discharges the discharged paper. There is a problem that the posture of the sheet that is pushed and discharged onto the discharge tray is disturbed.
[0012]
Therefore, the present invention has been made to solve the above-mentioned problems of the related art, and an object of the present invention is to provide a case where swelling or curling due to binding needles is present in a sheet discharged onto a discharge tray. However, an object of the present invention is to provide a sheet stacking device capable of discharging sheets onto the discharge tray in a good posture.
[0013]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 is a discharge tray for discharging the sheets on which images are formed in a stacked state, and a rear end portion of the sheets discharged on the discharge tray in a discharge direction. In the sheet stacking device provided with a pressing member for pressing, a plurality of the pressing members are arranged along a direction orthogonal to a paper discharging direction, and the plurality of pressing members are individually discharged onto a discharge tray. A sheet stacking device, which is urged to press a sheet that has been pressed.
[0014]
The invention described in claim 2 is characterized in that each of the pressing members is urged by an urging member so as to press the sheet discharged onto the discharge tray. Paper loading device.
[0015]
Furthermore, the invention described in claim 3 is the sheet stacking device according to claim 1, wherein the pressing member is configured by a member having elasticity.
[0016]
Further, according to the invention described in claim 4, the pressing member presses the sheet discharged onto the discharge tray at the time of discharging the sheet onto the discharge tray, and also presses the sheet onto the discharge tray. 4. The sheet stacking device according to claim 1, wherein the sheet discharged onto the discharge tray is pressed again after the discharging operation.
[0017]
Further, according to the invention described in claim 5, the discharge tray is configured to be offset by a predetermined amount in a direction orthogonal to the paper discharge direction, and the discharge tray is configured to be held for a second time by the pressing member. The sheet stacking device according to claim 4, wherein the offset operation is started after the pressing operation is performed.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings.
[0019]
Embodiment 1
FIG. 2 shows a sheet post-processing apparatus to which the sheet stacking apparatus according to the first embodiment of the present invention is applied.
[0020]
As shown in FIG. 2, the sheet post-processing apparatus 1 performs a punching process, a binding process, a saddle stitching process, and the like on a sheet on which an image is formed by an image forming apparatus such as a copying machine or a printer (not shown). It is configured to perform post-processing.
[0021]
The sheet post-processing apparatus 1 also includes an interposer 2 that appropriately supplies desired sheets such as a cover sheet and a sheet on which a color image has been formed at predetermined timing to the sheet on which an image is formed by the image forming apparatus. And a folding device 4 for performing a desired folding process such as Z-folding or C-folding on the sheet passing through the interface module 3.
[0022]
In the sheet post-processing apparatus 1, a sheet on which an image is formed by an image forming apparatus (not shown) is subjected to a punching process by a punch unit or a binding process by a stapler to create a sheet bundle or a booklet. In addition, a stack tray (discharge tray) to be offset can discharge a plurality of sheets by offsetting (shifting) each set.
[0023]
As shown in FIG. 2, the interface module 3 is provided with an inlet 5 on its left side into which a sheet on which an image is formed from an image forming apparatus (not shown) is introduced. Is provided with a carry-in roll 6 for carrying paper. On the downstream side of the carry-in roll 6, there is provided a discharge port 8 which is opened horizontally and horizontally via a paper transport path 7 which extends obliquely upward. A curl removing roll 9 for removing the curl is provided.
[0024]
Further, on the upper part of the interface module 3, an interposer 2 for appropriately supplying a desired sheet such as a cover sheet or a sheet on which a color image is formed with respect to a sheet on which an image is formed by the image forming apparatus is mounted. ing. The interposer 2 includes a paper feed tray 10 on which paper is loaded, and a nudger roll 11, a feed roll 12, a retard roll which feeds the paper loaded on the paper feed tray 10 one by one. A roll 13 and an exit roll 14 for discharging the fed paper to the interface module 3 are provided. Further, inside the interface module 3, a paper transport path 16 having a transport roll 15 for transporting the paper introduced from the interposer 2 to the discharge port 8 is provided.
[0025]
On the other hand, as shown in FIG. 2, the folding device 4 has an inlet 17 for introducing the paper discharged from the interface module 3 on the left side thereof, and has a horizontal direction on its right side. A discharge port 19 for discharging a sheet via the disposed sheet conveyance path 18 is provided. An introduction roll 20 is provided inside the introduction port 17, and a conveyance roll 21 is provided downstream of the introduction roll 20, and a folding paper conveyance path 22 branched downward is provided. It is provided vertically downward. The sheet introduced into the folding sheet transport path 22 is folded by a folding roll 24 in a state where the leading end thereof is abutted against an abutting portion 23, and then provided with a transport roll 25. The paper is conveyed to the tri-fold paper conveyance path 26. Then, the sheet conveyed to the three-fold sheet conveyance path 26 is subjected to a process of being folded into three by the folding roll 28 in a state where the leading end of the sheet is abutted against the abutting portion 27. Thereafter, the sheet that has been folded in three is conveyed to the discharge port 19 via the discharge sheet conveyance path 30 provided with the conveyance rolls 29. In the folding apparatus 4, as shown in FIG. 3, the sheet 90 can be C-folded or Z-folded.
[0026]
FIG. 2 also shows a sheet post-processing apparatus to which the sheet stacking apparatus according to the first embodiment of the present invention is applied.
[0027]
The paper post-processing apparatus 1 is provided on its left side with an inlet 31 for introducing the paper 90 that has passed through the folding processing apparatus 4, and inside the inlet 31, the paper 90 is inclined obliquely upward. An introduction roll 33 for transporting the paper along the paper transport path 32 is provided. Further, on the downstream side of the introduction roll 33, the sheet is conveyed by the introduction roll 33, and is also fed back by the reverse rotation roll 34 located further downstream, and the rear end portion is abutted against an abutting portion (not shown). A punch unit 35 is provided as a punching means for performing a punching process on a predetermined position of the sheet 90 whose skew has been corrected. Further, on the downstream side of the punch unit 35, the paper transport path is branched into two, and among the paper transport paths, the paper transport path 36 that is branched upward is a sheet on which a punching process is performed as necessary. This is for discharging the sheet 90 on which an image has been formed, as it is, to a fixed tray, performing binding processing, and performing offset discharge. On the other hand, among the above-described paper transport paths, the paper transport path 38 that is provided with the transport rolls 37 and that branches downward is subjected to a saddle stitching folding process in which the paper 90 is bound at the center and then folded at the binding portion. It is for doing.
[0028]
The paper transport path 36 branched upward is further branched into two, and the paper transport path 39 branched upward in the vertical direction is provided with a sheet 90 that has been subjected to perforation processing as necessary and an image is formed. This is for discharging the paper 90 as it is or for discharging unnecessary paper 90 onto the fixed tray 40. A transport roll 41 and a top discharge roll 42 are provided in the paper transport path 39, and a sheet 90 on which a perforation process has been performed, a sheet 90 on which an image is formed, and the like, as necessary, are fixed to a fixed tray 40. It is configured to be discharged.
[0029]
Further, among the paper transport paths branched upward, the paper transport path 43 further branched in a substantially horizontal direction performs a binding process along one edge of the paper 90 or a binding process at a corner, or a plurality of sheets. The sheet 90 is discharged in a state where it is offset for each set. A reverse rotation roll 44 for a buffer and a compile discharge roll 45 are disposed in the paper transport path 43, and the compile discharge roll 45 discharges the paper 90 onto the compile tray 46 in order. . Further, a predetermined number of sheets 90 aligned on the compile tray 46 are subjected to binding processing by a stapler 47 as necessary, and then discharged onto a stack tray 49 serving as a discharge tray offset by a discharge roll 48. Is done.
[0030]
At the base end of the compile tray 46, a guide member 50 for abutting the base end of the paper 90 is provided so as to be retractable, and a paddle 51 for aligning the paper 90 is provided rotatably. ing. Further, a tamper 52 for arranging the sheets 90 in the width direction is provided at an intermediate portion of the compile tray 46 so as to be movable in a direction perpendicular to the drawing. An auxiliary paddle 53 for arranging the sheets 90 and a retractable shelf member 54 for guiding the sheet bundle are provided at the leading end of the compile tray 46. Further, a clamper 55 as a holding member for suppressing the base end of the sheet 90 discharged onto the tray 49 is rotatably arranged at the base end of the stack tray 49.
[0031]
The discharge roll 48 and the auxiliary paddle 53 can be individually moved upward at a predetermined timing.
[0032]
Further, at the upper end of the paper transport path 36, a double transport path 56 branches downward, and a buffer roll 57 is provided in the double transport path 56.
[0033]
A discharge roll 61 for discharging the paper 90 onto the alignment tray 60 is provided below the paper transport path 38 branched from the downstream side of the punch unit 35. At the lower end, an end guide 62 that abuts against the lower end of the paper 90 is provided to be movable in the vertical direction. Further, a stapler 63 for saddle stitching, a tamper driving unit 64 for driving a tamper (not shown) for aligning the paper 90, and a folding knife unit for folding the aligned paper 90 at the center are provided in the middle of the alignment tray 60. 65 are provided. The paper 90 aligned on the alignment tray 60 is folded at the center by a folding knife section 65 and two sets of folding rolls 66, and then discharged onto a book tray 68 by an exit roll 67. It is configured to: Reference numeral 69 denotes a paddle provided above and below the alignment tray 60 for aligning the paper 90.
[0034]
By the way, in this embodiment, a paper stack having a discharge tray for discharging the paper on which an image is formed in a stacked state and a pressing member for pressing a rear end portion of the paper discharged on the discharge tray in a discharge direction is provided. In the apparatus, a plurality of the pressing members are arranged along a direction orthogonal to a sheet discharging direction, and the plurality of pressing members are urged to press the sheets individually discharged onto a discharge tray. It is characterized by having been done.
[0035]
In this embodiment, each of the pressing members is urged by an urging member so as to press the sheet discharged onto the discharge tray.
[0036]
Further, in this embodiment, the pressing member presses the sheet discharged onto the discharge tray during the operation of discharging the sheet onto the discharge tray, and after the operation of discharging the sheet onto the discharge tray, It is configured to press the sheet discharged onto the discharge tray again.
[0037]
In this embodiment, the discharge tray is configured to be offset by a predetermined amount in a direction orthogonal to the sheet discharge direction, and the discharge tray performs a second pressing operation by the pressing member. After that, the offset operation is started.
[0038]
That is, in the sheet stacking device 70 according to the present embodiment, as shown in FIG. 1, the sheet stacking device 70 corresponds to the rear end portion of the stack tray 49 as a discharge tray disposed so as to be able to move up and down in the vertical direction. A clamper 55 as a holding member is rotatably disposed at a rear end of the stack tray 49 in the discharge direction when the stack tray 49 moves to the uppermost end. As shown in FIG. 1, the clamper 55 is rotatably attached to the back surface of the end plate 71 of the stack tray 49 which is arranged to be able to move up and down.
[0039]
More specifically, as shown in FIG. 1, the end plate 71 is provided with three concave grooves 72 linearly formed in the vertical direction at predetermined intervals along the horizontal direction. As shown in FIG. 4, the clampers 55 are respectively mounted at positions corresponding to the upper ends of the concave grooves 72 along the axial direction of the rotating shaft 73.
[0040]
As shown in FIG. 5, these clampers 55 include a rear end portion 74 extending radially outward with respect to the rotation shaft 73 and a clockwise direction from the rear end portion 74 in the discharge direction. The intermediate portion 75 extends in a state of being curved along and radially outward, and a tip portion 76 extending radially outward from the intermediate portion 75 substantially tangentially to the rotation shaft 73. ing. A non-slip member 77 made of rubber or the like is fixed to the distal end portion 76 of the clamper 55. Further, as shown in FIG. 5, the clamper 55 is rotatably mounted over a predetermined angle with respect to the rotation shaft 73, and the clamper 55 is mounted on one side of the clamper 55 in a clockwise direction. An attachment member 78 for attaching a spring 80 as an urging member for urging is attached to the rotating shaft 73 in a fixed state. One end of each of the clampers 55 is locked by a projection 79 projecting from the intermediate portion 75 on the opposite side to the bending direction, and the other end is locked by a mounting member 78 as a biasing member. The coil spring 80 is configured to be individually urged clockwise in FIG.
[0041]
As shown in FIG. 6, a driving gear 81 is attached to one end of the rotating shaft 73 to which the clamper 55 is attached. Are engaged. The tip of an operating rod 84 of a solenoid 83 is connected to the fan-shaped gear 82, and the rotating shaft 73 is rotatable by turning on / off the solenoid 83. A member for driving the clamper 55 such as the solenoid 83 is mounted on the back surface of the end plate 71 as shown in FIG. Further, as shown in FIG. 6, a metal arm 85 is attached to the rotating shaft 73, and a compression spring 86 is attached to a distal end of the arm 85. , Are biased in a counterclockwise direction. Then, as shown in FIG. 7, the clamper 55 is rotatable between a separated position separated from the sheet 90 and a pressing position for pressing the sheet 90 by turning on / off the solenoid 83. The clamper 55 is urged to press the upper surface of the paper 90 so as to be rotatable by a predetermined angle at a holding position for pressing the paper 90.
[0042]
Further, in this embodiment, as shown in FIGS. 4 and 8, when the clamper 55 is offset at the retreat position separated from the sheet 90, it is configured not to contact the lower discharge roll 48. Further, as shown in FIG. 8, the clamper 55 is configured to abut on the rotating shaft 48a of the lower discharge roll 48 and stop at the retracted position separated from the paper 90. Further, the clamper 55 is disposed so as not to protrude from the running surface of the sheet 90 in an operation trajectory moving from the holding position to the retracted position. As a result, even when the clamper 55 is at a position retracted from the upper surface of the sheet 90, the clamper 55 does not hinder the ejection of the sheet 90.
[0043]
Further, in the sheet stacking device 70 according to this embodiment, as shown in FIG. 9, the stack tray 49 is disposed so as to be movable in the vertical direction, and the stack tray 49 It is arranged so that it can be offset along the direction orthogonal to.
[0044]
As shown in FIG. 9, the paper stacking device 70 includes a pair of side frames 91 and 92 fixed and arranged in parallel with each other on the in side and the out side. As shown in FIG. 1, the inner and outer side frames 91 and 92 are connected in parallel to each other by a plurality (three in the illustrated example) of connecting angle members 93 to 95. I have. An end frame 71 is slidably attached to the upper two connection angles 93 and 94 along the horizontal direction.
[0045]
Further, as shown in FIG. 9, a movable frame 96 having a substantially U-shaped cross section located at the rear end of the stack tray 49 in the discharge direction is provided between the inner and outer side frames 91 and 92. The movable frame 96 is movably mounted in the vertical direction along guide grooves 97 and 98 provided in the side frames 91 and 92 in a state of being inclined.
[0046]
A moving mechanism 99 for moving the moving frame 96 in the vertical direction is attached to one end of the moving frame 96 in the longitudinal direction. The moving mechanism 99 includes an elevator motor 100 and a gear train that reduces the rotational driving force of the elevator motor 100 and transmits the reduced rotational driving force to the pinion gear 101. As shown in FIGS. 1 and 9, the pinion gear 101 meshes with long rack gears 102 and 103 arranged along the guide grooves 97 and 98, and the one pinion gear 101 is connected to the elevator. When the motor 100 is driven to rotate in a predetermined direction, the moving frame 96 can be moved in the vertical direction.
[0047]
Further, as shown in FIG. 10, a stack tray 49 is slidably attached to the moving frame 96 via a guide rail 104 for linear sliding along a direction orthogonal to the discharge direction of the paper 90. . The stack tray 49 is connected to the end frame 71, and the stack tray 49 is slidable integrally with the end frame 71 in a direction orthogonal to the paper 90 discharge direction.
[0048]
Further, as described above, the end frame 71 is also slidably attached in a direction orthogonal to the paper 90 discharge direction. On the back side of the end frame 71, as shown in FIGS. 1 and 11, an offset motor 105 and a gear train 106 for reducing the rotational driving force of the offset motor 105 and transmitting the rotational driving force to the eccentric cam 107. Are arranged. By driving the offset motor 105 to rotate in a predetermined direction, the eccentric cam 107 is rotated by a predetermined amount, and the end guide 71 provided with the concave portion 108 in contact with the eccentric cam 107 is moved to the paper The stack tray 49 connected to the end guide 71 is offset by a predetermined amount in the direction orthogonal to the sheet discharge direction.
[0049]
When the end guide 71 moves in the direction perpendicular to the direction in which the sheet 90 is discharged as described above, the three clampers 55 attached to the end guide 71 also simultaneously move in the direction perpendicular to the direction in which the sheet 90 is discharged. It is configured to move along.
[0050]
As shown in FIGS. 1 and 9, the end guide 71 is provided with a groove 72 extending in the vertical direction at a position corresponding to the three clampers 55. Further, at the rear end of the stack tray 49 in the discharge direction, as shown in FIG. 12, a projection 111 is provided so as to correspond to the groove 110 of the end guide 71. In FIG. 12, reference numeral 112 denotes a tray support disposed below the stack tray 49.
[0051]
Further, as shown in FIG. 9, the upper and lower side frames 91 and 92 have a plurality of sheet height detection units for detecting the sheets or sheet bundles discharged onto the stack tray 49, as shown in FIG. Sensors 121 to 123 and a detection sensor 124 for detecting the position of the upper surface of the stack tray 49 are provided. The three sheet height detection sensors 121 to 123 are provided, and a first sheet height detection sensor 121, a second sheet height detection sensor 122, and a third sheet height detection sensor 123 are provided. Are configured to detect different sheet heights.
[0052]
As shown in FIG. 9, a mixed stack sensor 125 and a half stack sensor 126 are provided at the upper ends along the guide grooves 97 and 98 of the side frames 91 and 92 on the inner and outer sides. At its lower end, a full stack sensor 127 and a lower limit detection sensor 128 are provided.
[0053]
In the above configuration, the paper stacking apparatus according to the present embodiment can perform the discharging even if the paper discharged onto the discharge tray has a swelling or curling due to a binding needle as described below. The paper can be discharged onto the tray with good posture.
[0054]
That is, as shown in FIG. 2, the sheet post-processing apparatus to which the sheet stacking apparatus 70 according to this embodiment is applied includes a sheet 90 on which an image is formed by the image forming apparatus and the interface module 3 and the folding processing apparatus. 4 through an inlet 31 provided on the left side surface. The sheet 90 introduced into the sheet post-processing apparatus 1 is subjected to a predetermined punching process by the punch unit 35 or a binding process at one end edge or a corner portion by the stapler 47 as necessary. Alternatively, or as it is, the sheets are sequentially discharged onto a stack tray 49 as a discharge tray.
[0055]
At this time, as shown in FIG. 8, a plurality of clampers 55 as a pressing member for pressing the sheet 90 or a bundle of sheets 90 discharged onto the stack tray 49 are provided at the rear end of the stack tray 49 in the discharging direction. Are rotatably disposed.
[0056]
As shown in FIG. 5, the plurality of clampers 55 are rotatably mounted on the rotating shaft 73 over a predetermined angle, and are individually clockwise by a coil spring 80 as an urging means. Being energized.
[0057]
Therefore, as shown in FIG. 8, when the sheet 90 or the sheet bundle discharged onto the stack tray 49 is discharged onto the stack tray 49 by the discharge roll 48 (the upper roll is not shown), Each of the clampers 55 is discharged onto the stack tray 49 in a state where the clampers 55 are rotated counterclockwise and retracted. Thereafter, the sheet 90 or the bundle of sheets 90 discharged onto the stack tray 49 is pressed by the clamper 55 that rotates clockwise, as shown in FIG. The stapler 47 prevents the needle portion from rising and the paper 90 from being curled. In addition, since each of the clampers 55 is individually urged clockwise by the coil spring 80, the paper 90 or a bundle of papers may have a needle portion lifted by the stapler 47 or a paper 90 curled up. Even if there is, the sheet 90 or the sheet bundle can be reliably pressed at the position of each of the clampers 55. Further, as shown in FIGS. 1 and 4, the three clampers 55 are disposed at predetermined intervals along a direction orthogonal to the discharge direction of the paper 90, so that the discharge of the paper 90 is performed. Even if there is a curl or the like along a direction perpendicular to the direction, the three clampers 55 can reliably prevent the sheet from being lifted up, and do not hinder the next sheet 90 from being discharged. It is possible to discharge the sheet 90 with a good posture.
[0058]
More specifically, as shown in FIG. 14, before the discharge roller 48 is driven to rotate and the discharge of the paper 90 is started, the solenoid 83 is turned on, and the clamper 55 is already discharged onto the stack tray 49. Paper 90 is pressed. Then, immediately before the rear end of the sheet 90 passes through the nip portion of the discharge roller 48, the solenoid 83 is turned off just before the time when the clamper 55 returns to the retracted position, and the clamper 55 Separated from 90. The solenoid 83 discharges the sheet 90 onto the stack tray 49 due to the natural fall of the sheet 90 in anticipation of the time required for the sheet 90 discharged by the discharge roller 48 to be discharged to the top of the stack tray 49 by the natural fall due to its own weight. Then, the sheet 90 is turned on again, and operates so as to press the sheet 90 discharged onto the stack tray 49 by the clamper 55 together with the already discharged sheet 9 twice.
[0059]
The offset motor 105 is driven in a state where the sheet 90 discharged onto the stack tray 49 by the clamper 55 is pressed or separated from the sheet 90, so that the stack tray 49 is offset. .
[0060]
As described above, in the above-described embodiment, since the stack tray 49 is configured to start the offset operation after performing the second pressing operation by the clamper 55, the sheet discharged onto the stack tray 49 is configured. 90 can be more reliably prevented from rising.
[0061]
Embodiment 2
FIG. 15 shows another embodiment of the present invention. The same parts as those of the above embodiment are denoted by the same reference numerals. In the second embodiment, a clamper as a pressing member is provided. The configuration is different from that of the first embodiment.
[0062]
That is, in the second embodiment, as shown in FIG. 15, the clamper 55 as a pressing member is configured by a metal leaf spring fixed to the rotating shaft 73. And a non-slip member 77 made of rubber or the like.
[0063]
As described above, in the second embodiment, since the clampers 55 are formed of metal leaf springs, the individual clampers 55 themselves are urged in the direction of individually pressing the paper 90 by their own elasticity. ing.
[0064]
In the second embodiment, the configuration of the clamper 55 can be simplified, and the cost can be reduced.
[0065]
Other configurations and operations are the same as those in the first embodiment, and thus description thereof will be omitted.
[0066]
【The invention's effect】
As described above, according to the present invention, even when the paper discharged onto the discharge tray has a swelling or curl due to a binding staple, the paper can be discharged onto the discharge tray with good posture. A possible paper stacking device can be provided.
[Brief description of the drawings]
FIG. 1 is an external perspective view illustrating a main part of a sheet post-processing apparatus to which a sheet stacking apparatus according to a first embodiment of the present invention is applied.
FIG. 2 is an overall configuration diagram illustrating a sheet post-processing device to which the sheet stacking device according to the first embodiment of the present invention is applied;
FIG. 3 is an explanatory diagram showing a folding process in the folding device.
FIG. 4 is a configuration diagram showing an end plate and a clamper.
FIG. 5 is a configuration diagram showing a clamper.
FIG. 6 is a configuration diagram showing a driving mechanism of a clamper.
FIG. 7 is a configuration diagram showing a driving state of a clamper.
FIG. 8 is a configuration diagram showing an operation of the clamper.
FIG. 9 is an external perspective view illustrating a main part of a sheet post-processing device to which the sheet stacking device according to the first embodiment of the present invention is applied.
FIG. 10 is a configuration diagram showing a slide mechanism of a stack tray.
FIG. 11 is a configuration diagram showing a stack tray offset mechanism.
FIG. 12 is a configuration diagram illustrating a relationship between a stack tray and an end guide.
FIG. 13 is a configuration diagram showing a driving state of a clamper.
FIG. 14 is a timing chart showing the operation of the paper stacking device.
FIG. 15 is a configuration diagram showing a main part of a sheet stacking apparatus according to Embodiment 2 of the present invention.
[Explanation of symbols]
1: paper post-processing device, 49: stack tray, 55: clamper, 70: paper loading device, 71: end plate, 83: solenoid.

Claims (5)

In a sheet stacking device including a discharge tray that discharges sheets on which images are formed in a stacked state, and a pressing member that presses a rear end portion of the sheets discharged on the discharge tray in a discharge direction,
A plurality of the pressing members are arranged along a direction orthogonal to the sheet discharging direction, and the plurality of pressing members are urged to press the sheets discharged onto the discharge tray individually. A paper stacking device, characterized in that: 2. The sheet stacking device according to claim 1, wherein each of the pressing members is urged by an urging member to press the sheet discharged onto the discharge tray. 3. 2. The sheet stacking device according to claim 1, wherein the pressing member is formed of a member having elasticity. The pressing member presses the sheet discharged onto the discharge tray during the operation of discharging the sheet onto the discharge tray, and discharges the sheet onto the discharge tray again after the operation of discharging the sheet onto the discharge tray. The sheet stacking device according to any one of claims 1 to 3, wherein the pressed sheet is pressed. The discharge tray is configured to be offset by a predetermined amount in a direction orthogonal to the sheet discharge direction, and the discharge tray starts an offset operation after performing a second pressing operation by the pressing member. The sheet stacking device according to claim 4, wherein the sheet stacking device is configured as described above.

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