JP5109703B2 - Sheet alignment apparatus, post-processing apparatus, and image forming apparatus - Google Patents

Description

  The present invention relates to a sheet aligning device that aligns edges of sheets, a post-processing device having such a sheet aligning device, and an image forming apparatus having such a sheet aligning device.

  As a sheet aligning device, there is one that aligns the sheet by pushing the edge of the sheet one or more times by reciprocating movement of the aligning member, and such a sheet aligning device is used for a portion where the sheets are stacked on the discharge tray. .

  The sheet aligning apparatus is used as a pre-processing unit for these processes when performing a binding process or a folding process.

  A sheet aligning apparatus using a reciprocating aligning member is often used to perform alignment in a direction perpendicular to the sheet conveyance direction (hereinafter referred to as the width direction).

  Patent Documents 1 and 2 disclose such a sheet aligning apparatus.

  Patent Document 1 discloses a sheet aligning device in which an aligning member is connected to a support member via an elastic member, and the aligning member elastically pushes the sheet edge during the aligning operation.

  Patent Document 2 discloses a sheet aligning apparatus that uses an aligning member that is inclined inward, that is, on the side where a sheet exists.

The sheet aligning device of the patent branch 2 is intended to perform good alignment even for a curled sheet.
JP 2005-314092 A JP 2002-114433 A

  A problem in sheet alignment will be described with reference to FIG.

  The pair of alignment members 901 align the edges of the sheet S between the alignment members 901 in the direction indicated by the arrow X by an approach / separation operation.

  In the case of a flat sheet S with no curling, good alignment is performed. However, when the sheet S is curled as shown in the drawing, the upper surface SU is aligned with the alignment surface of the sheet SU and the alignment member 901. A gap G is formed between the two.

  As a result, the aligning action by the aligning member 901 does not reach the sheet SU above the stacking sheet apparatus or the aligning action becomes weak.

  Therefore, when the sheet has a curl, the alignment at the upper part of the stacked sheet is lowered.

  Although the figure shows a case of curl where the central part of the sheet is lowered, there is a problem that the alignment at the upper part of the stacked sheet is similarly lowered even when the curl is high in the central part.

  In Patent Document 1, sheet alignment is performed using an alignment member supported by an elastic member.

  However, in Patent Document 1, the alignment surface of the alignment member is in contact with the end portion of the sheet at a constant angle.

  For this reason, when aligning a sheet having curls, the alignment action on the sheet is different between the upper part and the lower part of the aligning member, and it is impossible to prevent misalignment.

  Further, Patent Document 2 proposes an alignment member whose upper part is inclined inward, that is, on the side where the sheet S is present.

  However, in Patent Document 2, since the alignment member is fixed to the support member, alignment is performed by pressing the end of the sheet with the alignment surface at a constant angle.

  Therefore, even in the aligning operation of the sheet aligning device described in Patent Document 2, the gap G shown in FIG.

  In particular, the sheet aligning apparatus of Patent Document 2 is effective for a sheet having a certain degree of curvature, but there is a problem in that the consistency decreases when the degree of curvature changes. Furthermore, the consistency changes depending on the amount of sheets.

  As described above, Patent Documents 1 and 2 disclose solutions to the problem of misalignment described with reference to FIG. 1, that is, the problem that misalignment occurs due to the formation of the gap G in the case of a curled sheet. Technology is inadequate.

  The present invention solves such a problem in the prior art and includes a sheet aligning device capable of performing high-precision alignment regardless of the curled state of the sheet, the accumulated amount of sheets, the paper quality, and the like, and the sheet aligning device. Another object of the present invention is to provide a post-processing apparatus and an image forming apparatus including the sheet aligning apparatus.

The object is achieved by the following invention.
1.
Seat support,
Proximity / reciprocates so as to separate a pair of aligning members for aligning the sheets by pressing both side edges of the sheets in the sheet support base on,
A support member for supporting each of the alignment members; and
An elastic member interposed between the alignment member and the support member;
The alignment member is connected to the support member via the elastic member a first portion far from the sheet support surface of the sheet support base, the second portion close to the sheet support surface is a free end,
When subjected to pressure of the seat in the integer case operation, wherein the second portion than the first portion, the sheet aligning apparatus characterized by largely displaced with respect to the support member.
2 .
A post-processing apparatus having the sheet aligning apparatus according to 1 and a processing unit that performs processes other than alignment.
3 .
2. An image forming apparatus comprising the sheet aligning device according to 1 and forming an image on a sheet subjected to alignment processing by the sheet aligning device.

  In the present invention, the alignment is performed by the alignment member that receives pressure from the sheet during the alignment operation and in which the first portion close to the sheet support surface is displaced more greatly.

  Therefore, a sheet aligning apparatus that performs high-precision alignment is realized regardless of differences in the degree of sheet curl, sheet amount, paper quality, and the like.

Although the present invention will be described based on the illustrated embodiment, the present invention is not limited to the embodiment.
<Image forming apparatus>
FIG. 1 is an overall view of an image forming apparatus according to an embodiment of the present invention including an image forming apparatus main body A and a post-processing apparatus FS.

  The illustrated image forming apparatus main body A includes an image reading unit 1, an image processing unit 2, an image writing unit 3, an image forming unit 4, a paper feed cassette 5, a paper feed unit 6, a fixing device 7, a paper discharge unit 8, an automatic unit. A double-sided copy paper feeding unit (ADU) 9 is provided.

  An automatic document feeder DF is mounted on the upper part of the image forming apparatus main body A. A post-processing device FS is connected to the paper discharge unit 8 side on the left side of the image forming apparatus main body A shown in the drawing.

  The document placed on the document table of the automatic document feeder DF is conveyed in the direction of the arrow, and an image on one or both sides of the document is read by the optical system of the image reading unit 1, and is read by the CCD image sensor 1A.

  The analog signal photoelectrically converted by the CCD image sensor 1A is subjected to analog processing, A / D conversion, shading correction, image compression processing, and the like in the image processing unit 2, and then sent to the image writing unit 3.

  At the time of image formation, output light is emitted from the semiconductor laser of the image writing unit 3, and the photosensitive drum 4A of the image forming unit 4 is irradiated to form a latent image. In the image forming unit 4, processes such as charging, exposure, development, transfer, separation, and cleaning are performed. The recording sheet S1 fed from the paper feed cassette 5 by the paper feed means 6 comes into contact with the photosensitive drum 4A in which the latent image is converted into a toner image by the development process, and the toner image is transferred by the transfer means 4B. The recording sheet S1 carrying the toner image is fixed by the fixing device 7 and sent from the paper discharge unit 8 to the post-processing device FS. In the case of double-sided copying, the recording sheet S1 that has undergone single-sided image processing is sent to the automatic double-sided copy paper feeding unit 9 by the conveyance path switching plate 8A, and image processing is performed again on the back side in the image forming unit 4 and fixed. The paper is discharged from the paper discharge unit 8.

  Next, a post-processing apparatus according to an embodiment of the present invention will be described with reference to FIG.

  The post-processing device FS includes a sheet carry-in unit 20, insertion paper feeding units 30a and 30b, and a plurality of post-processing units. The post-processing unit includes a punching processing unit 40, a folding processing unit 50, an overlay processing unit 60, staplers 71 and 72, and a paper discharge unit 80.

  The insertion sheet feeding unit 30a is loaded with the insertion sheet S2, and the insertion sheet feeding unit 30b is loaded with another insertion sheet S3.

  The insertion sheets S2 and S3 are insertion sheets such as a cover sheet and an insert sheet that are inserted into the recording sheet S1 discharged from the image forming apparatus main body A, and perform punching processing and folding processing similarly to the recording sheet S1. I can do it.

  The insertion sheets S2 and S3 sent out from the insertion sheet feeding sections 30a and 30b are conveyed to the sheet carry-in section 20 through a downward conveyance path (without reference numerals).

  The punching processing unit 40 is disposed in the sheet carry-in unit 20.

  In the following description, the recording sheet S1 and the insertion sheets S2 and S3 are collectively referred to as a sheet S.

  The folding processing unit 50 is disposed on a conveyance path H1 branched downward from the sheet carry-in unit 20.

  The overlapping processing unit 60 is disposed on the downstream side of the conveyance path H2 branched upward from the sheet carry-in unit 20, and includes conveyance paths H3, H4, and H5.

  In the stapler 71 located on the downstream side, the superimposing unit 60 waits the subsequent sheet S in the transport path H3 and the transport paths H4 and H5 in order to secure time for binding the preceding sheet S. .

  The conveyance path located on the downstream side of the conveyance path H2 is branched into a doubly curved conveyance path, and is divided into an inner conveyance path H4 and outer conveyance paths H3 and H5.

  A conveyance roller 21 is provided at the discharge port of the conveyance path H4 that forms an inner conveyance path that is branched from the conveyance path H2, and rotates when the first sheet S to be bound is conveyed. In a state in which the sheet is stopped, the leading edge of the sheet is received and is in a standby state in contact with the conveying roller 21.

  As described above, the sheet S conveyed on the conveyance path H2 waits with the leading end abutting against the conveyance roller 21, but the subsequent sheet S enters the conveyance path H3 from the conveyance path H2 and is conveyed to the conveyance roller. 21 is reached.

  From the conveying roller 21, the preceding sheet S and the succeeding sheet S are conveyed together and conveyed to the intermediate stacker 70.

  The conveyance path H3 is continuous with the conveyance path H2 downstream of the conveyance path H2, and the conveyance path H5 is continuous with the conveyance path H3.

  The conveyance path H3 is branched into a conveyance path H5 and a conveyance path H6.

  The conveyance path H <b> 6 forms a paper discharge path for discharging the sheet S to the fixed paper discharge tray 81.

  The fixed paper discharge tray 81 is disposed at a position protruding outside the post-processing device FS on the downstream side of the conveyance path H6 branched from the superposition processing unit 60 in the conveyance roller 24 on the conveyance path H3.

  As described above, the fixed paper discharge tray 81 is conveyed through the conveyance paths H2, H3, and H6 and accumulates the discharged sheets S.

  The paper discharge unit 80 includes a paper discharge roller 22 and discharges the sheet S to the lift paper discharge tray 82.

  The paper discharge roller 22 is composed of a pair of rollers. When the paper is not discharged, the pair of rollers are separated from each other.

  The sheet S conveyed by the conveyance roller 21 travels leftward between a pair of spaced apart rollers.

  When the trailing edge of the sheet S moves away from the conveying roller 21, the sheet S falls onto the intermediate stacker 70, slides down the inclined intermediate stacker 70, is received by the stopper 73, and stops at the intermediate stacker 70.

  When the set number of sheets S are stacked on the intermediate stacker 70, the stapler 71 operates to bind the sheets S.

  The bound sheet S is pushed up by the stopper 73 and moves to the upper left on the intermediate stacker 70.

  At this time, the pair of rollers constituting the paper discharge roller 22 come into contact, nip the sheet S, convey it, and discharge it to the lift paper discharge tray 82.

  In the folding mode, the sheet S is conveyed downward along the conveyance path H <b> 1 from the sheet carry-in unit 20, and is subjected to middle folding or tri-fold processing in the folding processing unit 50 and is discharged to the lower paper discharge tray 83.

  In the saddle stitching mode, the sheet S is conveyed from the sheet carry-in unit 20 through the conveyance path H1, is subjected to the saddle stitching process in the stapler 72, and is subjected to the middle folding process in the folding processing unit 50, and then the lower sheet discharge tray 83. To be discharged.

  A sheet aligning device 90 aligns the sheets S on the intermediate stacker 70.

There are the following four paths as the sheet S discharge path.
1) Sheet carry-in section 20 → conveyance path H2 → conveyance path H3 → conveyance path H6 → fixed discharge tray 81
2) Sheet carry-in section 20 → conveyance path H2 → conveyance paths H3, H4, H5 → intermediate stacker 70 → discharge section 80 → lifting / discharging tray 82
3) Sheet carry-in unit 20 → conveying path H2 → H4 → paper discharge unit 80 → lifting / discharging tray 82
4) Sheet carry-in unit 20 → conveying path H1 → folding processing unit 50 → lower sheet tray 83
The routes 1), 2) and 4) are as described above.

  The path 3) is selected when a large amount of image is formed without performing a binding process or a folding process.

  The sheet S is discharged to the elevating / discharging tray 82 without post-processing, and the elevating / discharging tray 82 is indicated by a chain line in the figure so that the uppermost surface of the discharged sheet S is always at a constant height. Move down to.

Accordingly, it is possible to stack thousands of sheets on the elevating / discharging tray 82.
<Sheet alignment device>
Hereinafter, a sheet aligning device 90 according to an embodiment of the present invention will be described.

  The sheet aligning device 90 performs alignment processing on the sheet placed on the intermediate stacker 70.

  One or two sheets S conveyed through the conveying paths H4 and H5 are discharged from the conveying roller 22.

  The sheet S discharged from the transport roller 22 passes through a gap between a pair of rollers constituting the paper discharge roller 23 and is transported outside the apparatus on the lift paper discharge tray 82.

  When the trailing edge of the sheet S leaves the conveyance roller 22, the sheet S falls on the intermediate stacker 70, is received by a stopper 73 provided on the intermediate stacker 70, and stops at a predetermined position.

  The sheet aligning device 90 performs an alignment operation each time a sheet is supplied to the intermediate stacker 70, that is, each time one or two sheets S are supplied to the intermediate stacker 70, and the sheet S is perpendicular to the transport direction. Align in the width direction.

  When the set number of sheets S are stacked on the intermediate stacker 70, the stapler 71 operates to perform a binding process in which a binding needle is driven into the bundle of sheets S.

  When the binding process is completed, the stopper 73 rises in the upper left direction and pushes up the bundle of sheets S.

  In synchronization with the push-up of the sheet S, a pair of rollers constituting the paper discharge roller 22 comes into pressure contact, teaches and rotates the bundle of sheets S, and discharges the bundle of sheets S to the lift paper discharge tray 82.

  FIG. 3 shows a sheet aligning apparatus according to Embodiment 1 of the present invention.

  The sheet aligning device 90 has a pair of aligning members 901 arranged in parallel in the width direction.

  The pair of alignment members 901 are supported by support members 902, respectively.

  The alignment member 901 is coupled to the support member 902 via an elastic member 903 at the upper portion thereof.

  The elastic member 903 is a member that connects the alignment member 901 to the support member 902 so that the lower portion is largely displaced with respect to the upper portion when receiving pressure, and is made of an elastic material such as a spring or rubber.

  The lower part of the alignment member 901 is a free end that can move freely.

  The pair of support members 902 are driven by the motor M to perform an operation of approaching / separating as indicated by an arrow X.

  As shown in FIG. 2, the inclined intermediate stacker 70 constitutes a sheet support base for supporting the aligned sheets.

  FIG. 4 shows the alignment operation of the sheet aligning device 90.

  In a state where the sheet S exists between the pair of alignment members 901, the pair of alignment members 901 receives pressure from the sheet S by the reciprocation of the support member 902.

  Due to this pressure, the alignment member 901 supported by the elastic member 903 escapes at the lower portion, which is a free end, as shown in the drawing, and as a result, tilts.

  That is, the second portion of the alignment member near the sheet support surface R of the intermediate stacker 70 is displaced more greatly with respect to the support member 902 than the first portion far from the sheet support surface R.

  Due to this inclination of the alignment member 901, even when the sheet S is curled as shown in the figure, no gap (gap G in FIG. 1) is formed between the alignment member 901 and the sheet S.

  The inclination angle of the alignment member 901 shown in FIG. 4 changes corresponding to the amount of sheet S interposed between the pair of alignment members 901, the curl state, the paper quality, and the like. Further, not only the angle but also the amount of displacement in the X direction changes according to the pressure received from the sheet S during alignment by the action of the elastic member 903.

  As a result, the gap G is not formed as shown in FIG. 1, and even when a large number of sheets S are stacked, the sheets are aligned well and misalignment is prevented.

  In the figure, a sheet having a curl whose center portion is high is illustrated, but even a sheet having a curl whose center portion is low can be similarly aligned.

  The illustrated embodiment is a sheet aligning device including a pair of aligning means having an aligning member 901, a support member 902, and an elastic member 903.

  However, the aligning device of FIG. 4 can be applied to a sheet aligning device that has one aligning means and presses the sheet S against a fixed wall by the aligning operation of the one aligning means.

  Alternatively, a pair of aligning means may be used, and only one aligning means may have an aligning member 901, a support member 902, and an elastic member 903 as shown in FIG.

  FIG. 5 shows a sheet aligning device 90 according to Embodiment 2 of the present invention.

  In the second embodiment, the alignment member 901 is connected to the support member 902 at the upper end portion by the connecting shaft 904, and the elastic member 905 is interposed between the alignment member 901 and the support member 902 at the lower end portion of the alignment member 901. .

  Similar to the elastic member 903, the elastic member 905 is formed of a spring or rubber.

  The alignment member 901 can rotate around the connecting shaft 904.

  When the alignment member 901 receives pressure from the accumulation sheet in the alignment operation, the alignment member 901 rotates and tilts about the connecting shaft 904.

  Therefore, as described above, good alignment is achieved even with a curled sheet.

  FIG. 6 shows a sheet aligning apparatus according to Embodiment 3 of the present invention.

  In the third embodiment, the pair of alignment members 901 are configured by leaf springs, and a base portion 901a that is a connecting portion with the support member 902 and an alignment member 901b that is bent from the base portion 901a and has a lower end formed at the free end. Have

  In the operation of performing the sheet alignment by performing the reciprocating operation indicated by the arrow X, the alignment member 901b is deformed by the pressure by the sheet, but the lower end portion (second portion) of the alignment member 901b is the upper end portion (first portion) with respect to the support member 902. Displaced more than 1 part).

  As a result, the surface of the alignment member 901b that comes into contact with the sheet is inclined, and a gap between the alignment member 901b and the sheet due to curling is not formed, and good alignment is performed.

It is a figure for demonstrating the problem in sheet alignment. 1 is an overall view of an image forming apparatus according to an embodiment of the present invention. It is a figure which shows the sheet aligning apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows matching operation | movement. It is a figure which shows the sheet aligning apparatus which concerns on Embodiment 2 of this invention. It is a figure which shows the sheet aligning apparatus which concerns on Embodiment 3 of this invention.

Explanation of symbols

A image forming apparatus main body FS post-processing apparatus 70 intermediate stacker 90 sheet aligning apparatus 901, 901b aligning member 902 supporting member 903, 905 elastic member 904 connecting shaft R sheet supporting surface S sheet

Claims (3)

Seat support,
Proximity / reciprocates so as to separate a pair of aligning members for aligning the sheets by pressing both side edges of the sheets in the sheet support base on,
A support member for supporting each of the alignment members; and
An elastic member interposed between the alignment member and the support member;
The alignment member is connected to the support member via the elastic member a first portion far from the sheet support surface of the sheet support base, the second portion close to the sheet support surface is a free end,
When subjected to pressure of the seat in the integer case operation, wherein the second portion than the first portion, the sheet aligning apparatus characterized by largely displaced with respect to the support member. A post-processing apparatus comprising the sheet aligning apparatus according to claim 1 and a processing unit that performs processes other than alignment. An image forming apparatus comprising the sheet aligning apparatus according to claim 1 , wherein an image is formed on a sheet subjected to alignment processing by the sheet aligning apparatus.

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