JP2015127116A - Sheet binding device, and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet binding device capable of improving accuracy for aligning a sheet bundle while increasing the sheet binding number.SOLUTION: The sheet binding device includes a staple tray 301 where a plurality of sheets P are loaded on a placing surface, sheet conveying means for conveying the sheet P on the staple tray 301, a sheet bundle aligning part 310 for aligning ends of the plurality of sheets P in the sheet conveying direction and ends of the plurality of sheets P in the sheet width direction to each other on the staple tray 301, and sheet bundle pressing means for pressing a sheet bundle Pb in the bundle width direction with a pair of pressing members. There is provided a moisture supply part 340 such as moisture supply means for supplying moisture to a sheet end of the sheet bundle Pb in which the ends of the plurality of sheets P in the sheet conveying direction and the ends of the plurality of sheets P in the sheet width direction are aligned to each other on the staple tray 301 by the sheet bundle aligning part 310.

Description

  The present invention relates to a sheet binding device that presses and binds a bundle of sheets composed of a plurality of sheets, and an image forming apparatus such as a printer, a copying machine, and a facsimile machine including the sheet binding device.

  In this type of paper binding device, without using a metal needle, a paper bundle is held by a pair of concavo-convex members such as a pair of pressure-bonding members that can engage with each other. The sheets are stretched and bound by binding the fibers of the sheets. In the sheet binding device, when the number of stacked sheets is increased, sufficient pressure cannot be applied to the sheet in the center of the sheet bundle, binding is insufficient, and the number of sheets bound is limited. As a method for increasing the number of sheets bound, the method described in Patent Document 1 is known.

  In the paper binding apparatus disclosed in Patent Document 1, moisture is supplied to the binding margin for each paper before being conveyed to the paper stacking table, and the sheets are sequentially stacked on the mounting surface of the paper stacking table. The sheet bundle direction is aligned by aligning the sheet conveyance direction end and the sheet width direction end of the sheet bundle. The aligned sheet bundle is bound and bonded in the bundle thickness direction by a pair of concave and convex members. By supplying moisture to the binding margin of the paper, the fibers of the paper can be loosened and the fibers of the paper can be intertwined deeply and intricately and bound firmly. Thereby, sufficient binding can be performed between sheets, and the number of sheets can be increased.

  However, in the paper binding apparatus disclosed in Patent Document 1, the papers after water supply are sequentially stacked on the placement surface of the paper stacking table, so that the papers stick to each other. Even if you try to align the end of the paper bundle in the paper transport direction and the end of the paper width direction, the papers are stuck together, making it difficult for the paper to slide. End up. As a result, there is a problem that the alignment accuracy of the sheet bundle is lowered.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a sheet binding device and an image forming apparatus capable of improving the alignment accuracy of a sheet bundle while increasing the number of sheets bound. is there.

  In order to achieve the above object, a first aspect of the present invention is a sheet stacking member on which a plurality of sheets are stacked on a placement surface, a sheet transporting means for transporting a sheet on the sheet stacking member, and the sheet An edge aligning unit that aligns the sheet conveying direction end and the sheet width direction end of the plurality of sheets on the stacking member; and a sheet bundle pressing unit that presses the sheet bundle in the bundle thickness direction with a pair of pressing members. In the sheet binding device, the sheet aligning unit includes a sheet conveying member and a sheet width direction end of the plurality of sheets aligned with each other on the sheet stacking member by the edge aligning unit. A water supply means for supplying is provided.

  According to the present invention, there is an excellent effect that the alignment accuracy of the sheet bundle can be improved while increasing the number of sheets bound.

1 is a diagram illustrating a configuration of an image forming system according to an embodiment. 2 is a schematic cross-sectional view illustrating a configuration of a sheet post-processing apparatus. It is a perspective view which shows the structure of the paper binding apparatus of this embodiment. (A) is a top view explaining the structure of a paper binding apparatus, (b) is a front view. It is a perspective view explaining a mode that a saddle sheet is inserted between sheets. FIG. 6 is a diagram for explaining a state of displacement of a leading end portion of a sheet at a notch portion of a staple tray. It is a figure explaining a mode that the clearance gap between sheets is expanded. It is a perspective view explaining a mode that a saddle sheet is evacuated from between sheets. It is a fragmentary perspective view explaining the structure of the modification 1 of a clearance gap expansion part. It is a fragmentary perspective view explaining the structure of the modification 2 of a clearance gap expansion part.

Hereinafter, an image forming system 1 according to an embodiment of the present invention will be described.
FIG. 1 is a diagram illustrating a configuration of an image forming system according to the embodiment. As shown in FIG. 1, the image forming system 1 includes an image forming apparatus 100 and a paper post-processing apparatus 200. The image forming apparatus 100 and the sheet post-processing apparatus 200 are connected to be able to communicate with each other. In the image forming system 1, the image forming apparatus 100 forms an image on the paper P, and the paper post-processing apparatus 200 receives the paper P from the image forming apparatus 100 and performs various post-processing on the received paper P. Examples of various post-processing to be performed on the received paper P include paper binding processing and half-folding processing.

  In the present embodiment, in the sheet binding process, the sheet post-processing apparatus 200 as a sheet binding apparatus binds a sheet bundle Pb formed by stacking a plurality of sheets P without using a stapler needle (metal needle). Further, the sheet post-processing apparatus 200 that performs various post-processing as described above has a non-staple mode, a staple mode, and a half-fold mode as operation modes. Further, a known configuration can be applied as the image forming apparatus 100, and in this embodiment, an electrophotographic color copier is provided. The image forming apparatus 100 includes, for example, a control unit, an image forming unit, an optical writing unit, a paper feeding unit, a paper feeding conveyance path, an image reading unit, an intermediate transfer unit, a fixing unit, a paper discharge conveyance path, a double-side conveyance path, and the like ( Both of them are not shown), and images are formed on both sides or one side of the paper P.

  An image forming apparatus 100 illustrated in FIG. 1 includes four image forming units 102 a, 102 b, 102 c, and 102 d arranged along the traveling direction of the transfer belt 109. The image forming unit 102a includes a photosensitive drum 103a as an image carrier, a drum charger 104a, an exposure device 105a, a developing device 106a, a transfer device 107a, a cleaning device 108a, and the like. The image forming units 102b to 102d are configured similarly to the 102a. The image forming units 102a to 102d form images of different colors, for example, 102a is yellow, 102b is magenta, 102c is cyan, and 102d is black.

  Upon receiving an image forming operation start instruction signal from a control unit (not shown) of the image forming apparatus, the photosensitive drum 103a starts rotating in the direction of arrow B in FIG. 1 and continues rotating until the image forming operation ends. . When the photosensitive drum 103a starts rotating, a high voltage is applied to the drum charger 104a, and negative charges are uniformly charged on the surface of the photosensitive drum 103a. Character data or graphic data converted into a dot image is sent to the image forming apparatus 100 from a control unit (not shown) of the image forming apparatus as an on / off signal of the exposure apparatus 105a. Then, on the surface of the photosensitive drum 103a, a portion irradiated with laser light from the exposure device 105a and a portion not irradiated are formed. When the portion where the charge is reduced on the photosensitive drum 103a reaches the position facing the developing unit 106a by the irradiation of the laser beam from the exposure device 105a, the portion where the charge is reduced on the photosensitive drum 103a is negatively charged. The attracted toner is attracted to form a toner image.

  When the toner image formed on the photosensitive drum 103a reaches the transfer device 107a as the primary transfer means, the toner image is rotated in the direction of arrow A in FIG. 1 by the action of a high voltage applied to the transfer device 107a. Is transferred onto the transfer belt 109. Note that the toner remaining without being transferred onto the photosensitive drum 103a even after passing through the transfer position (image transfer site) is cleaned by the cleaning device 108a and is prepared for the next image forming operation.

  The image forming operation is similarly performed in the image forming unit 102b following the image forming unit 102a, and the toner image formed on the photosensitive drum 103b is transferred onto the transfer belt 109 by the action of a high voltage applied to the transfer unit 107b. Transcribed. At this time, the timing at which the image formed by the image forming unit 102a and transferred onto the transfer belt 109 reaches the transfer device 107b, and the timing at which the toner image formed on the photosensitive drum 103b is transferred to the transfer belt 109. Adjust. As a result, the toner images formed by the image forming unit 102 a and the image forming unit 102 b overlap on the transfer belt 109. Similarly, a full color image is formed on the transfer belt 109 by superimposing the toner images formed by the image forming units 102 c and 102 d on the transfer belt 109.

  At the same time when the full-color image reaches the sheet transfer unit 110 as the secondary transfer unit, the sheet P as the recording medium conveyed from the sheet feeding unit 111 of the image forming apparatus in the direction of arrow C in FIG. 110 is reached. The full color image on the transfer belt 109 is transferred to the upper side of the paper P by the action of a high voltage applied to the paper transfer device 110. The paper P on which a full color image (unfixed toner image) is formed exits the secondary transfer nip and is then sent to the fixing device 114.

  The fixing device 114 includes a fixing roller 114a and a pressure roller 114b that is pressed toward the fixing roller 114a. The fixing roller 114a and the pressure roller 114b are in contact with each other to form a fixing nip, and the paper P is sandwiched therebetween. The fixing roller 114a has a heat source 114c as a heating means inside, and heats the fixing roller 114a by the heat generated by the heat source 114c. The heated fixing roller 114a applies heat to the sheet sandwiched in the fixing nip and heats it. The full color image on the paper is fixed by the influence of the heating and the nip pressure.

  On the other hand, after the full-color image passes through the paper transfer unit 110, toner that is not transferred is adhered onto the transfer belt 109, and the toner is cleaned by the belt cleaning mechanism 113.

  The paper P that has passed the fixing device 114 has a different path for conveyance depending on the discharge mode. In the case of single-sided printing, it is discharged face-up so that the surface with the full-color image fixed becomes the front surface, or discharged so that the surface with the full-color image fixed becomes the front surface. The face is discharged. In the case of face-up discharge, the sheet P that has passed through the fixing device 114 is conveyed as it is from the image forming apparatus 100 to the sheet post-processing apparatus 200 as indicated by the direction of arrow D in FIG. On the other hand, in the case of face-down discharge, after passing through the fixing device 114, it is sent toward the switchback portion 115 as shown by the direction of arrow E1 in FIG. Then, the paper P is reversed by the switchback unit 115 and conveyed from the image forming apparatus 100 to the paper post-processing apparatus 200 as indicated by the direction of the arrow E2 in FIG.

  In the case of duplex printing, the sheet P after passing through the fixing device 114 is conveyed from the switchback unit 115 to the duplex conveyance path 116 and returns to the sheet transfer unit 110 again as indicated by the direction of arrow F in FIG. . Thereafter, the full color image formed in the same manner as described above is transferred to the paper P and passes through the fixing device 114. As described above, the sheet P that has passed through the fixing device 114 can be discharged face-up and face-down discharged by inverting and discharging the sheet P by the switchback unit 115.

  FIG. 2 is a schematic cross-sectional view illustrating the configuration of the sheet post-processing apparatus of FIG. The paper post-processing apparatus 200 shown in FIG. 2 is provided with a first transport path Pt 1 for receiving the paper P discharged from the image forming apparatus 100 and discharging the paper P to the paper discharge tray 206. Further, a second transport path Pt2 is provided for branching from the first transport path Pt1 and performing a binding process or the like on the sheet bundle Pb. And the 1st conveyance path Pt1 and the 2nd conveyance path Pt2 comprise the conveyance part formed by several conveyance roller pairs 201-205,207-209, a guide member (not shown) etc., for example, and the branch nail | claw 210 As a result, the paper transport direction is switched to the first transport path Pt1 or the second transport path Pt2.

  In the first transport path Pt1, the transport roller pair 201, 202, the branch claw 210, the transport roller pair 203, 204, and the paper discharge roller pair 205 are arranged in this order in the upstream direction of the sheet transport direction of the first transport path Pt1 (hereinafter simply referred to as “simply”) It is arranged from the upstream side) to the downstream side in the paper conveyance direction (hereinafter simply referred to as the downstream side). The rollers of the conveyance roller pair 201 and 202, the conveyance roller pair 203 and 204, and the paper discharge roller pair 205 are rotationally driven by a motor (not shown) to convey the paper P. A conveyance sensor (not shown) is disposed on the upstream side of the conveyance roller pair 201, and the conveyance sensor detects that the sheet P has been carried into the sheet post-processing apparatus 200.

  Further, a branching claw 210 is disposed on the downstream side of the conveying roller pair 202. The branch claw 210 rotates and switches its posture so that the paper P transported from the upstream side is separated from the downstream portion of the branch claw 210 in the first transport path Pt1 and the second transport path Pt2. To either one of them. The branch claw 210 is driven by, for example, a motor or a solenoid.

  In the non-staple mode, the paper P carried into the first transport path Pt1 from the image forming apparatus 100 is transported by the transport roller pairs 201, 202, 203, and 204 and the discharge roller pair 205 and is discharged to the discharge tray 206. Is done. Further, in the staple mode, the paper P carried into the first transport path Pt1 is transported to the second transport path Pt2 with the advancing direction changed by the branching claw 210. In the second conveyance path Pt2, conveyance roller pairs 207 to 209 and a sheet binding device 300 are arranged. Each roller of the conveyance roller pairs 207 to 209 is driven by a motor (not shown) to convey the paper P.

  In the staple mode, the sheet bundle aligning unit 310 as a sheet aligning unit includes a staple tray 301, a first movable reference fence 311, and a second movable reference fence 312. The sheets P received from the image forming apparatus 100 are sequentially stacked on a staple tray 301 as a sheet stacking member of the sheet binding apparatus 300. As a result, the designated number (plurality) of sheets P are stacked to form a sheet bundle Pb. At this time, the first movable reference fence 311 provided in the sheet width direction perpendicular to the sheet conveyance direction of the staple tray 301 is brought into contact with both ends of each sheet P in the sheet width direction, respectively. Align. The leading end of each sheet P in the sheet conveyance direction is pressed against the second movable reference fence 312 provided on the downstream side in the sheet conveyance direction to align the sheet conveyance direction position of the sheet.

  The first movable reference fence 311 and the second movable reference fence 312 are driven by a motor (not shown) and can move to a predetermined position. The aligned sheet bundle Pb is pressed in the bundle thickness direction by a pressing member 321 of a sheet bundle pressing unit 320 as a sheet bundle pressing means. Next, a gap sheet 331 is inserted into the gap between the sheets by the gap enlargement unit 330 as a gap enlargement unit to enlarge the gap between the sheets. Water accumulated in the water supply tank 342 is sprayed by the nozzle 341 of the water supply unit 340 as a water supply unit from the gap, and water is supplied to the binding margin of the paper P. Thereafter, the sheet bundle Pb is bound by applying pressure at a sheet bundle crimping section (not shown). Further, water may be sprayed by the nozzle 341 on the bundle end portion side of the sheet bundle without expanding the gap between the sheets of the sheet bundle in the aligned state. In this case, moisture adhering to the edge of the paper penetrates into the paper. As a result, a bundle of sheets can be bound by loosening the fibers of the sheets and intertwining the fibers of the sheets.

  The bound sheet bundle Pb is transported to the third transport path Pt3 by the second movable reference fence 312. In the third conveyance path Pt3, a branching claw 211, conveyance roller pairs 212 to 214, and a discharge roller pair 215 are arranged, and each roller of the conveyance roller pairs 212 to 214 and the discharge roller pair 215 is driven by a motor (not shown). Is done. The bound sheet bundle Pb is conveyed by the rollers of the conveyance roller pairs 212 to 214 and the discharge roller pair 215 and discharged to the discharge tray 206.

  Further, the sheet post-processing apparatus 200 includes a control unit (not shown) that controls the operation of each unit. The control unit is a computer having a CPU, a storage unit, a communication interface, and the like. A conveyance sensor or the like is connected to the control unit. The control unit (CPU) drives and controls each unit of the sheet post-processing apparatus 200 in accordance with a program stored in the storage unit. Further, as described above, the control unit is connected to a control unit (not shown) of the image forming apparatus 100 so that data communication is possible.

FIG. 3 is a perspective view illustrating the configuration of the sheet binding device. FIG. 4 is a diagram illustrating the configuration of the sheet binding device. 4A is a plan view and FIG. 4B is a front view.
The sheet binding device 300 includes a sheet bundle aligning unit 310, a sheet bundle pressing unit 320, a gap expanding unit 330, a moisture supply unit 340, and a sheet bundle pressing unit. The sheet bundle aligning unit 310 as the edge aligning unit includes a first movable reference fence 311 and a second movable reference fence 312. A sheet bundle pressing unit 320 as a sheet pressing unit includes a pressing member 321 and a solenoid 322. The gap enlarging part 330 as the gap enlarging means has a ridge sheet 331 and a column 332 as insertion members. The water supply unit 340 as the water supply means includes a nozzle 341 and a water supply tank 342. As the sheet bundle crimping means, a sheet bundle crimping section (not shown) has a pair of concavo-convex members (not shown) and a pressure pump (not shown) that can engage with each other.

  As shown in FIGS. 3 and 4, a plurality of sheets P are conveyed in the direction of arrow G in FIGS. 3 and 4 on the loading surface of the staple tray 301. The plurality of conveyed sheets P are sequentially stacked on the loading surface of the staple tray 301 and stacked as a sheet bundle Pb. The first movable reference fence 311 is pressed against the end of the sheet bundle from the sheet width direction of the sheet bundle, and the end of the sheet bundle in the sheet transport direction is pressed against the second movable reference fence 312. Accordingly, the sheet conveyance direction end and the sheet width direction end of the sheet bundle Pb can be aligned with each other. Here, the sheet bundle aligning process may be performed every time the sheets are stacked, or the sheet bundle aligning process may be performed collectively after a predetermined number of sheets P are stacked. A sensor 313 that detects the passage of the paper P is provided at the tip of the first movable reference fence 311. Further, a nozzle 341 is provided at the tip of a pipe from the water supply tank 342 that stores water so that the amount of water can be adjusted by a pressure pump (not shown). When a predetermined number of sheets P are stacked on the loading surface of the staple tray 301 and water is sprayed from the nozzles 341 and water is supplied to the binding margin of the sheets P, the gap is widened in order to sufficiently and sufficiently supply water to the sheets P. The gap between the sheets is widened by the unit 330. The gap enlarging unit 330 inserts the eave sheet 331 into the gap between the sheets, and spreads the eave sheets 331 at regular intervals just before water supply to form a uniform gap between the sheets. Water can be supplied from the gap to the binding margin for each sheet.

  The eaves sheet 331 is inserted in the support column 332, and can perform an up-and-down operation and a rotation operation. These operations are performed by a motor or the like (not shown). Then, before widening the gap between the sheets by the gap enlargement unit 330, the sheet bundle Pb is pressed in the sheet bundle thickness direction by the pressing member 321 to maintain the alignment of the sheet bundle. The pressing member 321 performs a pressing operation by driving the solenoid 322. As shown in FIG. 3 and FIG. 4B, a notch 302 is formed in the staple tray 301 at a location corresponding to the area where the rivet sheet 331 is inserted between the sheets.

Next, a paper binding operation in the paper binding device of the present embodiment will be described.
FIG. 5 is a perspective view illustrating a state in which a saddle sheet is inserted between sheets in the sheet binding operation. FIG. 6 is a diagram for explaining how the leading edge of the paper is displaced at the notch of the staple tray. FIG. 7 is a diagram illustrating a state in which a gap between sheets is enlarged.

  As shown in FIG. 5, the first sheet P <b> 1 carried into the sheet binding device 300 moves on the placement surface of the staple tray 301 toward the second movable reference fence (not shown). When the sensor 313 detects the passage of the sheet P1, as shown in FIG. 5A, the bottom sheet 331a, which is the lowest sheet among the plurality of sheet provided on the column 332, starts to descend. When the first sheet P1 is abutted against a second movable reference fence (not shown), the saddle sheet 331a moves to a predetermined position on the upper surface of the sheet P1.

  Next, as shown in FIG. 5 (b), the next sheet P2 is subsequently conveyed, the sensor 313 detects the passage of the sheet P2, and the saddle sheet 331b starts to descend, and is stacked on the sheet P1. It moves to a predetermined position on the upper surface of the paper P2. By repeating this operation, the eaves sheet 331 is inserted between the sheets. At this time, as shown in FIGS. 6A and 6B, the sheets P <b> 1 and P <b> 2 that hang over the notch 302 hang down by their own weight at the notch 302 provided at the staple tray 301. When the paper sheet 331 is placed on the upper surface of the paper, the paper P1 further hangs down. As a result, the leading edge of the conveyed sheet is prevented from moving downward from the extension line extending in the moving direction of the leading edge and moving against the collar sheet 331. Yes. Thereafter, when a predetermined number of sheets P are stacked on the loading surface of the staple tray 301, the sheet bundle Pb is pressed from the sheet bundle thickness direction by a sheet bundle pressing unit (not shown), and the alignment of the sheet bundle Pb is maintained. . Thereafter, as shown in FIG. 7 (a), the flange sheets 331 inserted between the sheets are spread at a uniform interval by an elastic member (not shown) such as a leaf spring as shown in FIG. 7 (b). Form gaps that are evenly spaced.

  Here, when the sheet bundle Pb is pressed in the sheet bundle thickness direction by the pressing member 321, the position of the pressing member 321 is detected to detect the bundle thickness of the sheet bundle Pb. The thickness of one sheet is calculated from the detected bundle thickness and the number of sheets, and an appropriate amount of water supply is obtained for the thickness of the sheet. The amount of water jetted from the nozzle 341 is adjusted so that the calculated amount of water is jetted onto the paper. As a result, it is possible to supply water with a sufficient amount of water to prevent excessive water supply and perform sheet binding. In addition, since the amount of moisture absorbed by the fibers of the paper differs depending on the type of paper, the amount of water supplied may be adjusted according to the type of paper. Further, if the thickness and type of the paper are known in advance from the specification display printed on the paper package or the like, the amount of water supplied may be adjusted according to the thickness and type of the paper.

  Next, as shown in FIG. 8, after the water supply to the paper is completed, the bag sheet 331 is retracted from the gap between the paper and returned to the original position. Specifically, the eaves sheet 331 that has been inserted into the gap between the sheets is retracted from the gap between the sheets as the support column 332 rotates in the direction of the arrow H in FIG. At this time, the pressing member 321 holds the sheet bundle Pb in the sheet bundle thickness direction. Thus, the alignment of the sheet bundle is maintained so that the movement of the sheet does not occur when the reed sheet 331 is retracted by the action of the static frictional force between the reed sheet 331 and the sheet P. Further, as shown in FIG. 8, a water absorbing member 333 made of a water absorbing material is disposed at the retreat location of the dredging sheet 331, and the water absorption member 333 absorbs the remaining moisture of the dredging sheet 331, and the dredging sheet 331 is raised to the original position. To prepare for the next gap expansion operation. Thereby, it is possible to prevent the water adhering to the eaves sheet 331 during the gap expansion operation to be performed from being absorbed by the paper and causing excessive water supply. Thereafter, a sheet bundle binding process is performed by a sheet bundle crimping unit (not shown) in the next step. The bound sheet bundle Pb is transported by the second movable reference fence 312 to the third transport path Pt3 via the branching claw 211 of FIG. 2, and transported by the transport roller pairs 212 to 214 and the discharge roller pair 215 to be discharged. It is discharged to a paper tray 206.

(Modification 1)
Next, a modified example of the gap enlarging portion in the sheet binding device of the above embodiment (hereinafter, this modified example is referred to as “modified example 1”) will be described.
FIG. 9 is a partial perspective view illustrating a schematic configuration of Modification 1 of the gap enlargement portion. In the gap enlarging portion 400 of Modification 1 shown in FIG. 9, a plurality of plate materials 401 called paddles are arranged on the roller surface of the rotating roller 402 that rotates the shaft, and the plate surface of the plate material 401 is substantially parallel to the axial direction of the rotating roller 402. It is provided to become. The gap enlarging portion 400 in FIG. 9 is arranged so that the front end portion of the plate member 401 can touch the end portion of the sheet bundle Pb in which the end portion in the sheet conveyance direction and the end portion in the sheet width direction of the sheet P are aligned. Move in the direction of arrow I. Then, by rotating the rotating roller 402 by a motor (not shown) and rotating the plate member 401 in the direction of arrow J in FIG. 9, the leading end of the paper P is flipped up against the rigidity of the paper P. Increase the gap between paper. Further, the rotation roller 402 is rotated at a high speed so that the plurality of plate members 401 are brought into contact with the leading edge of the sheet P one after another, so that the leading edge of the sheet P is not returned to the original position, so that the gap between the sheets is reduced. Maintain an expanded state. Water is sprayed from the nozzle 341 through the gap to supply water to the binding margin of the paper P. The gap enlarging unit 400 is scanned in the sheet bundle thickness direction, and the position where the gap between the sheets is enlarged is changed by moving the jumping position by the plate material 401. As a result, even if the number of sheets to be bound increases, the gap between the sheets can be surely enlarged. Further, the water spray from the nozzle 341 may be performed continuously, or the water from the nozzle 341 is moved when the gap enlargement unit 400 moves to the target enlargement position in accordance with the enlargement position change by scanning of the gap enlargement unit 400. You may spray.

(Modification 2)
Next, another modified example (hereinafter, this modified example is referred to as “modified example 2”) of the gap enlargement unit in the sheet binding device of the above embodiment will be described.
FIG. 10 is a partial perspective view illustrating a schematic configuration of Modification 2 of the gap enlargement portion. In the gap enlargement unit 500 of the second modification shown in FIG. 10, the nozzle 501 has an air injection function in addition to the water injection function. By blowing air from the nozzle 501 to the gap between sheets of the sheet bundle Pb, the gap between sheets is expanded by air pressure. The injection direction of the nozzle 501 is inclined obliquely from the bottom to the top. Specifically, when the gap between sheets is enlarged, a switching valve (not shown) provided between the water supply tank 342 and a pressure pump (not shown) is connected between the pressure pump and the water supply tank 342. Switch to disconnect the communication and communicate with the atmosphere. The gap between the sheets is widened by blowing air upward from the nozzles 501 to the gaps between the sheets of the sheet bundle Pb. When the gap between the sheets is enlarged and water is supplied from the gap, the switching valve is switched so that the pressure pump and the water supply tank 342 communicate with each other, and water is ejected from the nozzle 501 to bind the sheet P. Supply water to The nozzle 501 may be configured to scan in the bundle thickness direction of the sheet bundle. In the case of this configuration, even when the bundle thickness of the sheet bundle is increased, a predetermined amount of air can be reliably injected into the gap between the sheets, and the gap between the sheets can be sufficiently enlarged. . Further, the nozzle for air injection is provided separately from the nozzle for water injection, so that water can be supplied to the paper substantially simultaneously with the enlargement of the gap between the paper. In the case of this configuration, the productivity of the sheet bundle can be improved.

What has been described above is merely an example, and the present invention has a specific effect for each of the following modes.
(Aspect 1)
A staple tray 301 such as a paper stacking member on which a plurality of sheets of paper P are stacked on the loading surface, a sheet transporting means for transporting the sheets P onto the staple tray 301, and a plurality of sheets of paper P on the staple tray 301. A sheet bundle aligning unit 310 such as an end aligning unit that aligns the sheet conveyance direction end and the sheet width direction end, and a sheet bundle crimping unit that crimps the sheet bundle Pb in the bundle thickness direction with a pair of crimping members. In the sheet binding device, moisture is supplied to the sheet end of the sheet bundle Pb in which the sheet conveyance direction ends and the sheet width direction ends of the plurality of sheets P are aligned with each other on the staple tray 301 by the sheet bundle aligning unit 310. A water supply unit 340 such as a water supply unit was provided.
According to this, as described in the above embodiment, by supplying moisture to the end of the sheet bundle Pb, the fibers of the sheet can be loosened, the entanglement of the fibers of the sheets can be improved, and the number of sheets bound can be increased. Can be increased. Further, before the moisture is supplied, it is easy to slide between the sheets, and the sheet bundle can be well aligned. For this reason, it is possible to improve the alignment accuracy of the sheet bundle as compared with the conventional configuration in which water is supplied for each sheet and the sheets are aligned after being stacked one by one. Therefore, it is possible to improve the alignment accuracy of the sheet bundle while increasing the number of sheets bound.
(Aspect 2)
In (Aspect 1), a sheet bundle pressing unit that presses the sheet bundle Pb in a state in which the sheet conveyance direction ends and the sheet width direction ends of the plurality of sheets P are aligned with each other by the sheet bundle aligning unit 310, and the like. The sheet bundle pressing unit 320 and the sheet bundle pressing unit 320 press the sheet bundle Pb in a state where the sheet conveyance direction end and the sheet width direction end of the plurality of sheets P are aligned with each other in the sheet bundle thickness direction. A gap enlarging unit 330 such as a gap enlarging means for enlarging a gap between the sheets P of the bundle Pb is provided.
According to this, as described in Example 1 of the above-described embodiment, by binding the paper P to the paper P in the paper bundle Pb, the binding allowance for each paper from the wide paper gap is increased. Sufficient water supply can be performed. Thereby, the number of sheets bound can be increased. By pressing the sheet bundle Pb in the sheet bundle thickness direction, it is possible to prevent the sheet P from moving and becoming unaligned when the gap between the sheets is enlarged.
(Aspect 3)
In (Aspect 2), the gap enlarging unit 330 includes a flange sheet 331 such as an insertion member that is inserted into a gap between sheets of the sheet bundle Pb stacked on the staple tray 301. According to this, as described in Example 1 of the above embodiment, necessary and sufficient moisture can be supplied to the sheet by expanding the gap between the sheets even after the sheet bundle is aligned.
(Aspect 4)
In any one of (Aspect 1) to (Aspect 3), the moisture supply unit 340 includes a nozzle 341 that injects water. According to this, as described in the above embodiment, it is possible to supply moisture evenly and sufficiently to the binding margin for each sheet.
(Aspect 5)
In any one of (Aspect 2) to (Aspect 4), a water absorbing member 333 such as a moisture removing member that removes moisture attached to the plate surface of the bag sheet 331 is provided. According to this, as described in the above-described embodiment, when the paper sheet 331 with moisture attached is inserted between the sheets and the water attached to the paper sheet 331 is absorbed by the paper P and water is supplied to the paper P, the water is excessive. There is a risk of water supply. Therefore, excessive water supply can be suppressed by absorbing and removing the water adhering to the bag sheet 331 by the water absorbing member 333.
(Aspect 6)
In (Aspect 2), the gap enlarging unit 400 is provided with a plate 401 on the roller surface of the rotating roller 402 that touches the leading edge of the sheet bundle Pb and displaces the leading edge of the sheet P in the gap expanding direction. As the rotation roller 402 rotates, the front end portion of the plate 401 is displaced in the gap expansion direction while making the front end portion of the paper P touchable. According to this, as described in Example 2 of the above-described embodiment, the gap between the sheets is increased by displacing the leading end of the sheet P in the gap increasing direction against the rigidity of the sheet P, thereby increasing the gap. Therefore, it is possible to supply the necessary and sufficient moisture. Further, by rotating the rotation roller 402 and causing the plate material 401 to come into contact with the leading edge of the paper P one after another, the leading edge of the paper P is not returned to the original position, and the expanded state of the gap between the papers is maintained. To do. The enlargement of the gap between the sheets and the water supply to the sheets can be performed substantially simultaneously, and the productivity of the sheet bundle can be improved.
(Aspect 7)
In (Aspect 2), the gap enlargement unit 500 includes a nozzle 501 such as an air supply unit that supplies air to the gap between sheets of the sheet bundle Pb. According to this, as described in Example 3 of the above embodiment, air is injected from the nozzles 501 into the gaps between the sheets of the sheet bundle Pb to apply air pressure to the gaps between the sheets. The gap is widened. Thereby, the gap between the sheets can be enlarged with a simple configuration, and the cost of the apparatus can be suppressed.
(Aspect 8)
In any one of (Aspect 1) to (Aspect 7), the water content is adjusted according to at least the type or thickness of the paper. According to this, as described in the above embodiment, it is possible to optimize the amount of water supplied to the paper for performing paper binding, enable optimal fiber loosening, and strengthen the fiber entanglement between papers can do.
(Aspect 9)
In an image forming apparatus having an image forming unit that forms an image on a sheet and a sheet binding unit that performs a binding process on the sheet after the image is formed by the image forming unit, The sheet binding device according to any one of modes 1) to (mode 8) is used. According to this, as described in the above embodiment, the sheet bundle alignment accuracy can be increased, and the reliability of the apparatus can be improved.

DESCRIPTION OF SYMBOLS 1 Image forming system 100 Image forming apparatus 200 Paper post-processing apparatus 300 Paper binding apparatus 301 Staple tray 302 Notch part 310 Paper bundle aligning part 311 1st movable reference fence 312 2nd movable reference fence 313 Sensor 320 Sheet bundle presser part 321 Presser Member 322 Solenoid 330 Gap enlargement part 331 Saddle sheet 332 Column 340 Water supply part 341 Nozzle 342 Water supply tank 400 Gap enlargement part 401 Plate material 402 Rotating roller 500 Gap enlargement part 501 Nozzle

JP 2001-301356 A

Claims (9)

A sheet stacking member on which a plurality of sheets are stacked on the loading surface, a sheet transporting means for transporting the sheet onto the sheet stacking member, and a sheet transport direction end of the plurality of sheets on the sheet stacking member And a sheet binding device comprising edge aligning means for aligning edges in the paper width direction with each other and paper bundle crimping means for crimping the sheet bundle in the bundle thickness direction with a pair of crimping members.
Moisture supply means for supplying moisture is provided to the sheet end of the sheet bundle in which the sheet conveyance direction end and the sheet width direction end of the plurality of sheets are aligned with each other on the sheet stacking member on the sheet stacking member. A sheet binding device characterized by that. The sheet binding device according to claim 1,
A sheet bundle pressing unit that presses the sheet bundle in the sheet bundle thickness direction in which the sheet conveying direction end and the sheet width direction end of the plurality of sheets are aligned with each other by the end aligning unit, and the sheet bundle pressing unit The gap that enlarges the gap between the sheets of the sheet bundle while pressing the sheet bundle in the sheet bundle thickness direction in which the sheet conveyance direction end and the sheet width direction end of the plurality of sheets are aligned with each other. A paper binding apparatus comprising: an enlarging unit. In the paper binding apparatus according to claim 2,
The paper gap binding device, wherein the gap enlarging means includes an insertion member that is inserted into a gap between paper sheets of a paper bundle stacked on the paper stacking member. In the paper binding apparatus according to any one of claims 1 to 3,
The paper binding device, wherein the water supply means includes a nozzle for jetting water. In the paper binding apparatus according to any one of claims 3 to 5,
A paper binding apparatus comprising a water removing member for removing water attached to the insertion member. In the paper binding apparatus according to claim 2,
The gap enlarging means is provided with a plate material on the roller surface of the rotating roller that touches the leading edge of the sheet of the bundle of paper and displaces the leading edge of the sheet in the gap expanding direction. The sheet binding device is characterized in that the front end portion of the plate member is displaced in the gap enlargement direction while making the front end portion of the paper accessible. In the paper binding apparatus according to claim 2,
The sheet binding device, wherein the gap enlarging means includes an air supply unit that supplies air to a gap between sheets of the sheet bundle. In the paper binding apparatus in any one of Claims 1-7,
A paper binding apparatus that adjusts the amount of water supplied by at least the type or thickness of the paper. An image forming apparatus comprising: an image forming unit that forms an image on a sheet; and a sheet binding unit that performs a binding process on the sheet after the image is formed by the image forming unit.
An image forming apparatus using the sheet binding device according to claim 1 as the sheet binding processing unit.

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